Update clang, llvm, lld, lldb, compiler-rt and libc++ to 4.0.0 release:

MFC r309142 (by emaste):

Add WITH_LLD_AS_LD build knob

If set it installs LLD as /usr/bin/ld.  LLD (as of version 3.9) is not
capable of linking the world and kernel, but can self-host and link many
substantial applications. GNU ld continues to be used for the world and
kernel build, regardless of how this knob is set.

It is on by default for arm64, and off for all other CPU architectures.

Sponsored by:	The FreeBSD Foundation

MFC r310840:

Reapply 310775, now it also builds correctly if lldb is disabled:

Move llvm-objdump from CLANG_EXTRAS to installed by default

We currently install three tools from binutils 2.17.50: as, ld, and
objdump. Work is underway to migrate to a permissively-licensed
tool-chain, with one goal being the retirement of binutils 2.17.50.

LLVM's llvm-objdump is intended to be compatible with GNU objdump
although it is currently missing some options and may have formatting
differences. Enable it by default for testing and further investigation.
It may later be changed to install as /usr/bin/objdump, it becomes a
fully viable replacement.

Reviewed by:	emaste
Differential Revision:	https://reviews.freebsd.org/D8879

MFC r312855 (by emaste):

Rename LLD_AS_LD to LLD_IS_LD, for consistency with CLANG_IS_CC

Reported by:	Dan McGregor <dan.mcgregor usask.ca>

MFC r313559 | glebius | 2017-02-10 18:34:48 +0100 (Fri, 10 Feb 2017) | 5 lines

Don't check struct rtentry on FreeBSD, it is an internal kernel structure.
On other systems it may be API structure for SIOCADDRT/SIOCDELRT.

Reviewed by:	emaste, dim

MFC r314152 (by jkim):

Remove an assembler flag, which is redundant since r309124.  The upstream
took care of it by introducing a macro NO_EXEC_STACK_DIRECTIVE.

http://llvm.org/viewvc/llvm-project?rev=273500&view=rev

Reviewed by:	dim

MFC r314564:

Upgrade our copies of clang, llvm, lld, lldb, compiler-rt and libc++ to
4.0.0 (branches/release_40 296509).  The release will follow soon.

Please note that from 3.5.0 onwards, clang, llvm and lldb require C++11
support to build; see UPDATING for more information.

Also note that as of 4.0.0, lld should be able to link the base system
on amd64 and aarch64.  See the WITH_LLD_IS_LLD setting in src.conf(5).
Though please be aware that this is work in progress.

Release notes for llvm, clang and lld will be available here:
<http://releases.llvm.org/4.0.0/docs/ReleaseNotes.html>
<http://releases.llvm.org/4.0.0/tools/clang/docs/ReleaseNotes.html>
<http://releases.llvm.org/4.0.0/tools/lld/docs/ReleaseNotes.html>

Thanks to Ed Maste, Jan Beich, Antoine Brodin and Eric Fiselier for
their help.

Relnotes:	yes
Exp-run:	antoine
PR:		215969, 216008

MFC r314708:

For now, revert r287232 from upstream llvm trunk (by Daniil Fukalov):

  [SCEV] limit recursion depth of CompareSCEVComplexity

  Summary:
  CompareSCEVComplexity goes too deep (50+ on a quite a big unrolled
  loop) and runs almost infinite time.

  Added cache of "equal" SCEV pairs to earlier cutoff of further
  estimation. Recursion depth limit was also introduced as a parameter.

  Reviewers: sanjoy

  Subscribers: mzolotukhin, tstellarAMD, llvm-commits

  Differential Revision: https://reviews.llvm.org/D26389

This commit is the cause of excessive compile times on skein_block.c
(and possibly other files) during kernel builds on amd64.

We never saw the problematic behavior described in this upstream commit,
so for now it is better to revert it.  An upstream bug has been filed
here: https://bugs.llvm.org/show_bug.cgi?id=32142

Reported by:	mjg

MFC r314795:

Reapply r287232 from upstream llvm trunk (by Daniil Fukalov):

  [SCEV] limit recursion depth of CompareSCEVComplexity

  Summary:
  CompareSCEVComplexity goes too deep (50+ on a quite a big unrolled
  loop) and runs almost infinite time.

  Added cache of "equal" SCEV pairs to earlier cutoff of further
  estimation. Recursion depth limit was also introduced as a parameter.

  Reviewers: sanjoy

  Subscribers: mzolotukhin, tstellarAMD, llvm-commits

  Differential Revision: https://reviews.llvm.org/D26389

Pull in r296992 from upstream llvm trunk (by Sanjoy Das):

  [SCEV] Decrease the recursion threshold for CompareValueComplexity

  Fixes PR32142.

  r287232 accidentally increased the recursion threshold for
  CompareValueComplexity from 2 to 32.  This change reverses that
  change by introducing a separate flag for CompareValueComplexity's
  threshold.

The latter revision fixes the excessive compile times for skein_block.c.

MFC r314907 | mmel | 2017-03-08 12:40:27 +0100 (Wed, 08 Mar 2017) | 7 lines

Unbreak ARMv6 world.

The new compiler_rt library imported with clang 4.0.0 have several fatal
issues (non-functional __udivsi3 for example) with ARM specific instrict
functions. As temporary workaround, until upstream solve these problems,
disable all thumb[1][2] related feature.

MFC r315016:

Update clang, llvm, lld, lldb, compiler-rt and libc++ to 4.0.0 release.
We were already very close to the last release candidate, so this is a
pretty minor update.

Relnotes:	yes

MFC r316005:

Revert r314907, and pull in r298713 from upstream compiler-rt trunk (by
Weiming Zhao):

  builtins: Select correct code fragments when compiling for Thumb1/Thum2/ARM ISA.

  Summary:
  Value of __ARM_ARCH_ISA_THUMB isn't based on the actual compilation
  mode (-mthumb, -marm), it reflect's capability of given CPU.

  Due to this:
   - use  __tbumb__ and __thumb2__ insteand of __ARM_ARCH_ISA_THUMB
   - use '.thumb' directive consistently  in all affected files
   - decorate all thumb functions using
     DEFINE_COMPILERRT_THUMB_FUNCTION()

  ---------
  Note: This patch doesn't fix broken Thumb1 variant of __udivsi3 !

  Reviewers: weimingz, rengolin, compnerd

  Subscribers: aemerson, dim

  Differential Revision: https://reviews.llvm.org/D30938

Discussed with:	mmel

1 files changed, 108 insertions, 26 deletions

diff --git a/contrib/llvm/tools/clang/lib/Basic/VirtualFileSystem.cpp b/contrib/llvm/tools/clang/lib/Basic/VirtualFileSystem.cpp
index 8ace2b3..50fcb22 100644
--- a/contrib/llvm/tools/clang/lib/Basic/VirtualFileSystem.cpp
+++ b/contrib/llvm/tools/clang/lib/Basic/VirtualFileSystem.cpp
@@ -47,7 +47,7 @@ Status::Status(const file_status &Status)
       User(Status.getUser()), Group(Status.getGroup()), Size(Status.getSize()),
       Type(Status.type()), Perms(Status.permissions()), IsVFSMapped(false)  {}
 
-Status::Status(StringRef Name, UniqueID UID, sys::TimeValue MTime,
+Status::Status(StringRef Name, UniqueID UID, sys::TimePoint<> MTime,
                uint32_t User, uint32_t Group, uint64_t Size, file_type Type,
                perms Perms)
     : Name(Name), UID(UID), MTime(MTime), User(User), Group(Group), Size(Size),
@@ -494,8 +494,8 @@ public:
 
 InMemoryFileSystem::InMemoryFileSystem(bool UseNormalizedPaths)
     : Root(new detail::InMemoryDirectory(
-          Status("", getNextVirtualUniqueID(), llvm::sys::TimeValue::MinTime(),
-                 0, 0, 0, llvm::sys::fs::file_type::directory_file,
+          Status("", getNextVirtualUniqueID(), llvm::sys::TimePoint<>(), 0, 0,
+                 0, llvm::sys::fs::file_type::directory_file,
                  llvm::sys::fs::perms::all_all))),
       UseNormalizedPaths(UseNormalizedPaths) {}
 
@@ -532,7 +532,7 @@ bool InMemoryFileSystem::addFile(const Twine &P, time_t ModificationTime,
         // End of the path, create a new file.
         // FIXME: expose the status details in the interface.
         Status Stat(P.str(), getNextVirtualUniqueID(),
-                    llvm::sys::TimeValue(ModificationTime, 0), 0, 0,
+                    llvm::sys::toTimePoint(ModificationTime), 0, 0,
                     Buffer->getBufferSize(),
                     llvm::sys::fs::file_type::regular_file,
                     llvm::sys::fs::all_all);
@@ -545,9 +545,9 @@ bool InMemoryFileSystem::addFile(const Twine &P, time_t ModificationTime,
       // FIXME: expose the status details in the interface.
       Status Stat(
           StringRef(Path.str().begin(), Name.end() - Path.str().begin()),
-          getNextVirtualUniqueID(), llvm::sys::TimeValue(ModificationTime, 0),
-          0, 0, Buffer->getBufferSize(),
-          llvm::sys::fs::file_type::directory_file, llvm::sys::fs::all_all);
+          getNextVirtualUniqueID(), llvm::sys::toTimePoint(ModificationTime), 0,
+          0, Buffer->getBufferSize(), llvm::sys::fs::file_type::directory_file,
+          llvm::sys::fs::all_all);
       Dir = cast<detail::InMemoryDirectory>(Dir->addChild(
           Name, llvm::make_unique<detail::InMemoryDirectory>(std::move(Stat))));
       continue;
@@ -801,6 +801,7 @@ public:
 ///   'case-sensitive': <boolean, default=true>
 ///   'use-external-names': <boolean, default=true>
 ///   'overlay-relative': <boolean, default=false>
+///   'ignore-non-existent-contents': <boolean, default=true>
 ///
 /// Virtual directories are represented as
 /// \verbatim
@@ -860,6 +861,14 @@ class RedirectingFileSystem : public vfs::FileSystem {
   /// \brief Whether to use to use the value of 'external-contents' for the
   /// names of files.  This global value is overridable on a per-file basis.
   bool UseExternalNames = true;
+
+  /// \brief Whether an invalid path obtained via 'external-contents' should
+  /// cause iteration on the VFS to stop. If 'true', the VFS should ignore
+  /// the entry and continue with the next. Allows YAML files to be shared
+  /// across multiple compiler invocations regardless of prior existent
+  /// paths in 'external-contents'. This global value is overridable on a
+  /// per-file basis.
+  bool IgnoreNonExistentContents = true;
   /// @}
 
   /// Virtual file paths and external files could be canonicalized without "..",
@@ -878,9 +887,6 @@ private:
   RedirectingFileSystem(IntrusiveRefCntPtr<FileSystem> ExternalFS)
       : ExternalFS(std::move(ExternalFS)) {}
 
-  /// \brief Looks up \p Path in \c Roots.
-  ErrorOr<Entry *> lookupPath(const Twine &Path);
-
   /// \brief Looks up the path <tt>[Start, End)</tt> in \p From, possibly
   /// recursing into the contents of \p From if it is a directory.
   ErrorOr<Entry *> lookupPath(sys::path::const_iterator Start,
@@ -890,6 +896,9 @@ private:
   ErrorOr<Status> status(const Twine &Path, Entry *E);
 
 public:
+  /// \brief Looks up \p Path in \c Roots.
+  ErrorOr<Entry *> lookupPath(const Twine &Path);
+
   /// \brief Parses \p Buffer, which is expected to be in YAML format and
   /// returns a virtual file system representing its contents.
   static RedirectingFileSystem *
@@ -937,6 +946,10 @@ public:
     return ExternalContentsPrefixDir;
   }
 
+  bool ignoreNonExistentContents() const {
+    return IgnoreNonExistentContents;
+  }
+
 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
 LLVM_DUMP_METHOD void dump() const {
     for (const std::unique_ptr<Entry> &Root : Roots)
@@ -1060,8 +1073,9 @@ class RedirectingFileSystemParser {
 
     // ... or create a new one
     std::unique_ptr<Entry> E = llvm::make_unique<RedirectingDirectoryEntry>(
-        Name, Status("", getNextVirtualUniqueID(), sys::TimeValue::now(), 0, 0,
-                     0, file_type::directory_file, sys::fs::all_all));
+        Name,
+        Status("", getNextVirtualUniqueID(), std::chrono::system_clock::now(),
+               0, 0, 0, file_type::directory_file, sys::fs::all_all));
 
     if (!ParentEntry) { // Add a new root to the overlay
       FS->Roots.push_back(std::move(E));
@@ -1262,8 +1276,8 @@ class RedirectingFileSystemParser {
     case EK_Directory:
       Result = llvm::make_unique<RedirectingDirectoryEntry>(
           LastComponent, std::move(EntryArrayContents),
-          Status("", getNextVirtualUniqueID(), sys::TimeValue::now(), 0, 0, 0,
-                 file_type::directory_file, sys::fs::all_all));
+          Status("", getNextVirtualUniqueID(), std::chrono::system_clock::now(),
+                 0, 0, 0, file_type::directory_file, sys::fs::all_all));
       break;
     }
 
@@ -1279,8 +1293,8 @@ class RedirectingFileSystemParser {
       Entries.push_back(std::move(Result));
       Result = llvm::make_unique<RedirectingDirectoryEntry>(
           *I, std::move(Entries),
-          Status("", getNextVirtualUniqueID(), sys::TimeValue::now(), 0, 0, 0,
-                 file_type::directory_file, sys::fs::all_all));
+          Status("", getNextVirtualUniqueID(), std::chrono::system_clock::now(),
+                 0, 0, 0, file_type::directory_file, sys::fs::all_all));
     }
     return Result;
   }
@@ -1301,6 +1315,7 @@ public:
       KeyStatusPair("case-sensitive", false),
       KeyStatusPair("use-external-names", false),
       KeyStatusPair("overlay-relative", false),
+      KeyStatusPair("ignore-non-existent-contents", false),
       KeyStatusPair("roots", true),
     };
 
@@ -1359,6 +1374,9 @@ public:
       } else if (Key == "use-external-names") {
         if (!parseScalarBool(I->getValue(), FS->UseExternalNames))
           return false;
+      } else if (Key == "ignore-non-existent-contents") {
+        if (!parseScalarBool(I->getValue(), FS->IgnoreNonExistentContents))
+          return false;
       } else {
         llvm_unreachable("key missing from Keys");
       }
@@ -1588,6 +1606,47 @@ vfs::getVFSFromYAML(std::unique_ptr<MemoryBuffer> Buffer,
                                        std::move(ExternalFS));
 }
 
+static void getVFSEntries(Entry *SrcE, SmallVectorImpl<StringRef> &Path,
+                          SmallVectorImpl<YAMLVFSEntry> &Entries) {
+  auto Kind = SrcE->getKind();
+  if (Kind == EK_Directory) {
+    auto *DE = dyn_cast<RedirectingDirectoryEntry>(SrcE);
+    assert(DE && "Must be a directory");
+    for (std::unique_ptr<Entry> &SubEntry :
+         llvm::make_range(DE->contents_begin(), DE->contents_end())) {
+      Path.push_back(SubEntry->getName());
+      getVFSEntries(SubEntry.get(), Path, Entries);
+      Path.pop_back();
+    }
+    return;
+  }
+
+  assert(Kind == EK_File && "Must be a EK_File");
+  auto *FE = dyn_cast<RedirectingFileEntry>(SrcE);
+  assert(FE && "Must be a file");
+  SmallString<128> VPath;
+  for (auto &Comp : Path)
+    llvm::sys::path::append(VPath, Comp);
+  Entries.push_back(YAMLVFSEntry(VPath.c_str(), FE->getExternalContentsPath()));
+}
+
+void vfs::collectVFSFromYAML(std::unique_ptr<MemoryBuffer> Buffer,
+                             SourceMgr::DiagHandlerTy DiagHandler,
+                             StringRef YAMLFilePath,
+                             SmallVectorImpl<YAMLVFSEntry> &CollectedEntries,
+                             void *DiagContext,
+                             IntrusiveRefCntPtr<FileSystem> ExternalFS) {
+  RedirectingFileSystem *VFS = RedirectingFileSystem::create(
+      std::move(Buffer), DiagHandler, YAMLFilePath, DiagContext,
+      std::move(ExternalFS));
+  ErrorOr<Entry *> RootE = VFS->lookupPath("/");
+  if (!RootE)
+    return;
+  SmallVector<StringRef, 8> Components;
+  Components.push_back("/");
+  getVFSEntries(*RootE, Components, CollectedEntries);
+}
+
 UniqueID vfs::getNextVirtualUniqueID() {
   static std::atomic<unsigned> UID;
   unsigned ID = ++UID;
@@ -1619,7 +1678,7 @@ public:
   JSONWriter(llvm::raw_ostream &OS) : OS(OS) {}
   void write(ArrayRef<YAMLVFSEntry> Entries, Optional<bool> UseExternalNames,
              Optional<bool> IsCaseSensitive, Optional<bool> IsOverlayRelative,
-             StringRef OverlayDir);
+             Optional<bool> IgnoreNonExistentContents, StringRef OverlayDir);
 };
 }
 
@@ -1675,6 +1734,7 @@ void JSONWriter::write(ArrayRef<YAMLVFSEntry> Entries,
                        Optional<bool> UseExternalNames,
                        Optional<bool> IsCaseSensitive,
                        Optional<bool> IsOverlayRelative,
+                       Optional<bool> IgnoreNonExistentContents,
                        StringRef OverlayDir) {
   using namespace llvm::sys;
 
@@ -1692,6 +1752,9 @@ void JSONWriter::write(ArrayRef<YAMLVFSEntry> Entries,
     OS << "  'overlay-relative': '"
        << (UseOverlayRelative ? "true" : "false") << "',\n";
   }
+  if (IgnoreNonExistentContents.hasValue())
+    OS << "  'ignore-non-existent-contents': '"
+       << (IgnoreNonExistentContents.getValue() ? "true" : "false") << "',\n";
   OS << "  'roots': [\n";
 
   if (!Entries.empty()) {
@@ -1748,7 +1811,8 @@ void YAMLVFSWriter::write(llvm::raw_ostream &OS) {
   });
 
   JSONWriter(OS).write(Mappings, UseExternalNames, IsCaseSensitive,
-                       IsOverlayRelative, OverlayDir);
+                       IsOverlayRelative, IgnoreNonExistentContents,
+                       OverlayDir);
 }
 
 VFSFromYamlDirIterImpl::VFSFromYamlDirIterImpl(
@@ -1756,29 +1820,47 @@ VFSFromYamlDirIterImpl::VFSFromYamlDirIterImpl(
     RedirectingDirectoryEntry::iterator Begin,
     RedirectingDirectoryEntry::iterator End, std::error_code &EC)
     : Dir(_Path.str()), FS(FS), Current(Begin), End(End) {
-  if (Current != End) {
+  while (Current != End) {
     SmallString<128> PathStr(Dir);
     llvm::sys::path::append(PathStr, (*Current)->getName());
     llvm::ErrorOr<vfs::Status> S = FS.status(PathStr);
-    if (S)
+    if (S) {
       CurrentEntry = *S;
-    else
+      return;
+    }
+    // Skip entries which do not map to a reliable external content.
+    if (FS.ignoreNonExistentContents() &&
+        S.getError() == llvm::errc::no_such_file_or_directory) {
+      ++Current;
+      continue;
+    } else {
       EC = S.getError();
+      break;
+    }
   }
 }
 
 std::error_code VFSFromYamlDirIterImpl::increment() {
   assert(Current != End && "cannot iterate past end");
-  if (++Current != End) {
+  while (++Current != End) {
     SmallString<128> PathStr(Dir);
     llvm::sys::path::append(PathStr, (*Current)->getName());
     llvm::ErrorOr<vfs::Status> S = FS.status(PathStr);
-    if (!S)
-      return S.getError();
+    if (!S) {
+      // Skip entries which do not map to a reliable external content.
+      if (FS.ignoreNonExistentContents() &&
+          S.getError() == llvm::errc::no_such_file_or_directory) {
+        continue;
+      } else {
+        return S.getError();
+      }
+    }
     CurrentEntry = *S;
-  } else {
-    CurrentEntry = Status();
+    break;
   }
+
+  if (Current == End)
+    CurrentEntry = Status();
   return std::error_code();
 }