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* Move all sources from the llvm project into contrib/llvm-project.Dimitry Andric2019-12-201-3187/+0
| | | | | | | | | | | | | This uses the new layout of the upstream repository, which was recently migrated to GitHub, and converted into a "monorepo". That is, most of the earlier separate sub-projects with their own branches and tags were consolidated into one top-level directory, and are now branched and tagged together. Updating the vendor area to match this layout is next. Notes: svn path=/head/; revision=355940
* Merge llvm trunk r366426, resolve conflicts, and update FREEBSD-Xlist.Dimitry Andric2019-08-211-32/+48
| | | | Notes: svn path=/projects/clang900-import/; revision=351344
* Merge llvm trunk r351319, resolve conflicts, and update FREEBSD-Xlist.Dimitry Andric2019-01-201-16/+31
| | | | Notes: svn path=/projects/clang800-import/; revision=343210
* Merge llvm trunk r338150 (just before the 7.0.0 branch point), andDimitry Andric2018-08-021-23/+42
| | | | | | | resolve conflicts. Notes: svn path=/projects/clang700-import/; revision=337149
* Merge llvm trunk r338150, and resolve conflicts.Dimitry Andric2018-07-301-77/+153
| | | | Notes: svn path=/projects/clang700-import/; revision=336916
* Upgrade our copies of clang, llvm, lld, lldb, compiler-rt and libc++ toDimitry Andric2018-02-021-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 6.0.0 (branches/release_60 r324090). This introduces retpoline support, with the -mretpoline flag. The upstream initial commit message (r323155 by Chandler Carruth) contains quite a bit of explanation. Quoting: Introduce the "retpoline" x86 mitigation technique for variant #2 of the speculative execution vulnerabilities disclosed today, specifically identified by CVE-2017-5715, "Branch Target Injection", and is one of the two halves to Spectre. Summary: First, we need to explain the core of the vulnerability. Note that this is a very incomplete description, please see the Project Zero blog post for details: https://googleprojectzero.blogspot.com/2018/01/reading-privileged-memory-with-side.html The basis for branch target injection is to direct speculative execution of the processor to some "gadget" of executable code by poisoning the prediction of indirect branches with the address of that gadget. The gadget in turn contains an operation that provides a side channel for reading data. Most commonly, this will look like a load of secret data followed by a branch on the loaded value and then a load of some predictable cache line. The attacker then uses timing of the processors cache to determine which direction the branch took *in the speculative execution*, and in turn what one bit of the loaded value was. Due to the nature of these timing side channels and the branch predictor on Intel processors, this allows an attacker to leak data only accessible to a privileged domain (like the kernel) back into an unprivileged domain. The goal is simple: avoid generating code which contains an indirect branch that could have its prediction poisoned by an attacker. In many cases, the compiler can simply use directed conditional branches and a small search tree. LLVM already has support for lowering switches in this way and the first step of this patch is to disable jump-table lowering of switches and introduce a pass to rewrite explicit indirectbr sequences into a switch over integers. However, there is no fully general alternative to indirect calls. We introduce a new construct we call a "retpoline" to implement indirect calls in a non-speculatable way. It can be thought of loosely as a trampoline for indirect calls which uses the RET instruction on x86. Further, we arrange for a specific call->ret sequence which ensures the processor predicts the return to go to a controlled, known location. The retpoline then "smashes" the return address pushed onto the stack by the call with the desired target of the original indirect call. The result is a predicted return to the next instruction after a call (which can be used to trap speculative execution within an infinite loop) and an actual indirect branch to an arbitrary address. On 64-bit x86 ABIs, this is especially easily done in the compiler by using a guaranteed scratch register to pass the target into this device. For 32-bit ABIs there isn't a guaranteed scratch register and so several different retpoline variants are introduced to use a scratch register if one is available in the calling convention and to otherwise use direct stack push/pop sequences to pass the target address. This "retpoline" mitigation is fully described in the following blog post: https://support.google.com/faqs/answer/7625886 We also support a target feature that disables emission of the retpoline thunk by the compiler to allow for custom thunks if users want them. These are particularly useful in environments like kernels that routinely do hot-patching on boot and want to hot-patch their thunk to different code sequences. They can write this custom thunk and use `-mretpoline-external-thunk` *in addition* to `-mretpoline`. In this case, on x86-64 thu thunk names must be: ``` __llvm_external_retpoline_r11 ``` or on 32-bit: ``` __llvm_external_retpoline_eax __llvm_external_retpoline_ecx __llvm_external_retpoline_edx __llvm_external_retpoline_push ``` And the target of the retpoline is passed in the named register, or in the case of the `push` suffix on the top of the stack via a `pushl` instruction. There is one other important source of indirect branches in x86 ELF binaries: the PLT. These patches also include support for LLD to generate PLT entries that perform a retpoline-style indirection. The only other indirect branches remaining that we are aware of are from precompiled runtimes (such as crt0.o and similar). The ones we have found are not really attackable, and so we have not focused on them here, but eventually these runtimes should also be replicated for retpoline-ed configurations for completeness. For kernels or other freestanding or fully static executables, the compiler switch `-mretpoline` is sufficient to fully mitigate this particular attack. For dynamic executables, you must compile *all* libraries with `-mretpoline` and additionally link the dynamic executable and all shared libraries with LLD and pass `-z retpolineplt` (or use similar functionality from some other linker). We strongly recommend also using `-z now` as non-lazy binding allows the retpoline-mitigated PLT to be substantially smaller. When manually apply similar transformations to `-mretpoline` to the Linux kernel we observed very small performance hits to applications running typic al workloads, and relatively minor hits (approximately 2%) even for extremely syscall-heavy applications. This is largely due to the small number of indirect branches that occur in performance sensitive paths of the kernel. When using these patches on statically linked applications, especially C++ applications, you should expect to see a much more dramatic performance hit. For microbenchmarks that are switch, indirect-, or virtual-call heavy we have seen overheads ranging from 10% to 50%. However, real-world workloads exhibit substantially lower performance impact. Notably, techniques such as PGO and ThinLTO dramatically reduce the impact of hot indirect calls (by speculatively promoting them to direct calls) and allow optimized search trees to be used to lower switches. If you need to deploy these techniques in C++ applications, we *strongly* recommend that you ensure all hot call targets are statically linked (avoiding PLT indirection) and use both PGO and ThinLTO. Well tuned servers using all of these techniques saw 5% - 10% overhead from the use of retpoline. We will add detailed documentation covering these components in subsequent patches, but wanted to make the core functionality available as soon as possible. Happy for more code review, but we'd really like to get these patches landed and backported ASAP for obvious reasons. We're planning to backport this to both 6.0 and 5.0 release streams and get a 5.0 release with just this cherry picked ASAP for distros and vendors. This patch is the work of a number of people over the past month: Eric, Reid, Rui, and myself. I'm mailing it out as a single commit due to the time sensitive nature of landing this and the need to backport it. Huge thanks to everyone who helped out here, and everyone at Intel who helped out in discussions about how to craft this. Also, credit goes to Paul Turner (at Google, but not an LLVM contributor) for much of the underlying retpoline design. Reviewers: echristo, rnk, ruiu, craig.topper, DavidKreitzer Subscribers: sanjoy, emaste, mcrosier, mgorny, mehdi_amini, hiraditya, llvm-commits Differential Revision: https://reviews.llvm.org/D41723 MFC after: 3 months X-MFC-With: r327952 PR: 224669 Notes: svn path=/head/; revision=328817
* Merge llvm trunk r321017 to contrib/llvm.Dimitry Andric2017-12-201-96/+109
| | | | Notes: svn path=/projects/clang600-import/; revision=327023
* Merge llvm, clang, lld, lldb, compiler-rt and libc++ r307894, and updateDimitry Andric2017-07-131-3/+2
| | | | | | | build glue. Notes: svn path=/projects/clang500-import/; revision=320970
* Merge llvm, clang, lld, lldb, compiler-rt and libc++ r306325, and updateDimitry Andric2017-06-271-19/+18
| | | | | | | build glue. Notes: svn path=/projects/clang500-import/; revision=320397
* Merge llvm, clang, lld, lldb, compiler-rt and libc++ r305145, and updateDimitry Andric2017-06-101-1/+1
| | | | | | | build glue. Notes: svn path=/projects/clang500-import/; revision=319799
* Merge llvm, clang, lld, lldb, compiler-rt and libc++ r304460, and updateDimitry Andric2017-06-011-7/+2
| | | | | | | build glue. Notes: svn path=/projects/clang500-import/; revision=319479
* Merge llvm, clang, lld, lldb, compiler-rt and libc++ r302418, and updateDimitry Andric2017-05-081-0/+4
| | | | | | | build glue. Notes: svn path=/projects/clang500-import/; revision=317969
* Merge llvm, clang, lld, lldb, compiler-rt and libc++ r301441, and updateDimitry Andric2017-04-261-13/+15
| | | | | | | build glue. Notes: svn path=/projects/clang500-import/; revision=317472
* Merge llvm, clang, lld and lldb trunk r300890, and update build glue.Dimitry Andric2017-04-201-6/+3
| | | | Notes: svn path=/projects/clang500-import/; revision=317230
* Merge llvm trunk r300422 and resolve conflicts.Dimitry Andric2017-04-161-39/+78
| | | | Notes: svn path=/projects/clang500-import/; revision=317029
* Merge llvm, clang, lld and lldb trunk r291012, and resolve conflicts.Dimitry Andric2017-01-041-8/+14
| | | | Notes: svn path=/projects/clang400-import/; revision=311327
* Update llvm to trunk r290819 and resolve conflicts.Dimitry Andric2017-01-021-120/+131
| | | | Notes: svn path=/projects/clang400-import/; revision=311142
* Update llvm to release_39 branch r276489, and resolve conflicts.Dimitry Andric2016-08-161-125/+398
| | | | Notes: svn path=/projects/clang390-import/; revision=304240
* Undo r295543, since the shrink wrapping bug was fixed upstream by DavideDimitry Andric2016-02-241-4/+0
| | | | | | | Italiano and Quentin Colombet. Notes: svn path=/projects/clang380-import/; revision=296008
* Update llvm and clang to release_38 branch r261369.Dimitry Andric2016-02-211-7/+6
| | | | Notes: svn path=/projects/clang380-import/; revision=295859
* For now, disable shrink-wrapping (a new optimization pass that computesDimitry Andric2016-02-111-0/+4
| | | | | | | | | | the safe point to insert the prologue and epilogue of the function) on X86. This prevents problems with some functions using TLS, such as in jemalloc, and which was the cause for Address Sanitizer crashes. The correct fix is still being discussed upstream. Notes: svn path=/projects/clang380-import/; revision=295543
* Update llvm and clang to release_38 branch r258549.Dimitry Andric2016-01-221-1/+17
| | | | Notes: svn path=/projects/clang380-import/; revision=294609
* Update llvm, clang and lldb to release_38 branch r257836.Dimitry Andric2016-01-161-6/+7
| | | | Notes: svn path=/projects/clang380-import/; revision=294170
* Update llvm to trunk r256945.Dimitry Andric2016-01-061-28/+6
| | | | Notes: svn path=/projects/clang380-import/; revision=293265
* Update llvm to trunk r256633.Dimitry Andric2015-12-301-191/+967
| | | | Notes: svn path=/projects/clang380-import/; revision=292941
* Update llvm, clang and lldb to 3.7.0 release.Dimitry Andric2015-09-061-0/+2
| | | | Notes: svn path=/projects/clang370-import/; revision=287521
* Update llvm/clang to r242221.Dimitry Andric2015-08-121-8/+21
| | | | Notes: svn path=/projects/clang-trunk/; revision=286684
* Update llvm/clang to r240225.Dimitry Andric2015-06-231-285/+208
| | | | Notes: svn path=/projects/clang-trunk/; revision=284734
* Merge llvm trunk r238337 from ^/vendor/llvm/dist, resolve conflicts, andDimitry Andric2015-05-271-351/+372
| | | | | | | preserve our customizations, where necessary. Notes: svn path=/projects/clang-trunk/; revision=283631
* Upgrade our copy of clang and llvm to 3.6.1 release.Dimitry Andric2015-05-251-25/+59
| | | | | | | | | | | | | | | | | | | | | | | | | | | This release contains the following cherry-picked revisions from upstream trunk: 226124 226151 226164 226165 226166 226407 226408 226409 226652 226905 226983 227084 227087 227089 227208 227209 227210 227211 227212 227213 227214 227269 227430 227482 227503 227519 227574 227822 227986 227987 227988 227989 227990 228037 228038 228039 228040 228188 228189 228190 228273 228372 228373 228374 228403 228765 228848 228918 229223 229225 229226 229227 229228 229230 229234 229235 229236 229238 229239 229413 229507 229680 229750 229751 229752 229911 230146 230147 230235 230253 230255 230469 230500 230564 230603 230657 230742 230748 230956 231219 231237 231245 231259 231280 231451 231563 231601 231658 231659 231662 231984 231986 232046 232085 232142 232176 232179 232189 232382 232386 232389 232425 232438 232443 232675 232786 232797 232943 232957 233075 233080 233351 233353 233409 233410 233508 233584 233819 233904 234629 234636 234891 234975 234977 235524 235641 235662 235931 236099 236306 236307 Please note that from 3.5.0 onwards, clang and llvm require C++11 support to build; see UPDATING for more information. Notes: svn path=/head/; revision=283526
* Pull in r227752 from upstream llvm trunk (by Michael Kuperstein):Dimitry Andric2015-02-021-124/+41
| | | | | | | | | | | | | | | | | | | | [X86] Convert esp-relative movs of function arguments to pushes, step 2 This moves the transformation introduced in r223757 into a separate MI pass. This allows it to cover many more cases (not only cases where there must be a reserved call frame), and perform rudimentary call folding. It still doesn't have a heuristic, so it is enabled only for optsize/minsize, with stack alignment <= 8, where it ought to be a fairly clear win. (Re-commit of r227728) Differential Revision: http://reviews.llvm.org/D6789 This helps to get sys/boot/i386/boot2 below the required size again, when optimizing with -Oz. Notes: svn path=/projects/clang360-import/; revision=278112
* Merge llvm 3.6.0rc1 from ^/vendor/llvm/dist, merge clang 3.6.0rc1 fromDimitry Andric2015-01-251-106/+401
| | | | | | | ^/vendor/clang/dist, resolve conflicts, and cleanup patches. Notes: svn path=/projects/clang360-import/; revision=277718
* Merge llvm 3.5.0 release from ^/vendor/llvm/dist, resolve conflicts, andDimitry Andric2014-11-241-202/+381
| | | | | | | preserve our customizations, where necessary. Notes: svn path=/projects/clang350-import/; revision=274968
* Pull in r196939 from upstream llvm trunk (by Reid Kleckner):Dimitry Andric2014-03-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Reland "Fix miscompile of MS inline assembly with stack realignment" This re-lands commit r196876, which was reverted in r196879. The tests have been fixed to pass on platforms with a stack alignment larger than 4. Update to clang side tests will land shortly. Pull in r196986 from upstream llvm trunk (by Reid Kleckner): Revert the backend fatal error from r196939 The combination of inline asm, stack realignment, and dynamic allocas turns out to be too common to reject out of hand. ASan inserts empy inline asm fragments and uses aligned allocas. Compiling any trivial function containing a dynamic alloca with ASan is enough to trigger the check. XFAIL the test cases that would be miscompiled and add one that uses the relevant functionality. Pull in r202930 from upstream llvm trunk (by Hans Wennborg): Check for dynamic allocas and inline asm that clobbers sp before building selection dag (PR19012) In X86SelectionDagInfo::EmitTargetCodeForMemcpy we check with MachineFrameInfo to make sure that ESI isn't used as a base pointer register before we choose to emit rep movs (which clobbers esi). The problem is that MachineFrameInfo wouldn't know about dynamic allocas or inline asm that clobbers the stack pointer until SelectionDAGBuilder has encountered them. This patch fixes the problem by checking for such things when building the FunctionLoweringInfo. Differential Revision: http://llvm-reviews.chandlerc.com/D2954 Together, these commits fix the problem encountered in the devel/emacs port on the i386 architecture, where a combination of stack realignment, alloca() and memcpy() could incidentally clobber the %esi register, leading to segfaults in the temacs build-time utility. See also: http://llvm.org/PR18171 and http://llvm.org/PR19012 Reported by: ashish PR: ports/183064 MFC after: 1 week Notes: svn path=/head/; revision=263312
* Upgrade our copy of llvm/clang to 3.4 release. This version supportsDimitry Andric2014-02-161-306/+31
| | | | | | | | | | | | | | | | | | | | all of the features in the current working draft of the upcoming C++ standard, provisionally named C++1y. The code generator's performance is greatly increased, and the loop auto-vectorizer is now enabled at -Os and -O2 in addition to -O3. The PowerPC backend has made several major improvements to code generation quality and compile time, and the X86, SPARC, ARM32, Aarch64 and SystemZ backends have all seen major feature work. Release notes for llvm and clang can be found here: <http://llvm.org/releases/3.4/docs/ReleaseNotes.html> <http://llvm.org/releases/3.4/tools/clang/docs/ReleaseNotes.html> MFC after: 1 month Notes: svn path=/head/; revision=261991
* Upgrade our copy of llvm/clang to 3.3 release.Dimitry Andric2013-06-121-33/+31
| | | | | | | | | Release notes are still in the works, these will follow soon. MFC after: 1 month Notes: svn path=/head/; revision=251662
* Upgrade our copy of llvm/clang to trunk r178860, in preparation of theDimitry Andric2013-04-121-43/+299
| | | | | | | | | | | | upcoming 3.3 release (branching and freezing expected in a few weeks). Preliminary release notes can be found at the usual location: <http://llvm.org/docs/ReleaseNotes.html> An MFC is planned once the actual 3.3 release is finished. Notes: svn path=/head/; revision=249423
* Upgrade our copy of llvm/clang to r168974, from upstream's release_32Dimitry Andric2012-12-031-8/+5
| | | | | | | | branch. This is effectively llvm/clang 3.2 RC2; the 3.2 release is coming soon. Notes: svn path=/head/; revision=243830
* Upgrade our copy of llvm/clang to trunk r162107. With thanks toDimitry Andric2012-08-201-61/+106
| | | | | | | Benjamin Kramer and Joerg Sonnenberger for their input and fixes. Notes: svn path=/head/; revision=239462
* Upgrade our copy of llvm/clang to trunk r154661, in preparation of theDimitry Andric2012-04-161-144/+236
| | | | | | | | | | upcoming 3.1 release (expected in a few weeks). Preliminary release notes can be found at: <http://llvm.org/docs/ReleaseNotes.html> MFC after: 2 weeks Notes: svn path=/head/; revision=234353
* Upgrade our copy of llvm/clang to r142614, from upstream's release_30Dimitry Andric2011-10-221-190/+427
| | | | | | | | | | branch. This brings us very close to the 3.0 release, which is expected in a week or two. MFC after: 1 week Notes: svn path=/head/; revision=226633
* Upgrade our copy of llvm/clang to r135360, from upstream's trunk.Dimitry Andric2011-07-171-7/+194
| | | | Notes: svn path=/head/; revision=224145
* Upgrade our copy of llvm/clang to r132879, from upstream's trunk.Dimitry Andric2011-06-121-1/+1
| | | | Notes: svn path=/head/; revision=223017
* Upgrade our copy of llvm/clang to r130700, from upstream's trunk.Dimitry Andric2011-05-021-65/+94
| | | | Notes: svn path=/head/; revision=221345
* Upgrade our copy of llvm/clang to r126079, from upstream's trunk.Dimitry Andric2011-02-201-0/+994
This contains many improvements, primarily better C++ support, an integrated assembler for x86 and support for -pg. Notes: svn path=/head/; revision=218893
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