MFC r309124:

Upgrade our copies of clang, llvm, lldb, compiler-rt and libc++ to 3.9.0
release, and add lld 3.9.0.  Also completely revamp the build system for
clang, llvm, lldb and their related tools.

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

Release notes for llvm, clang and lld are available here:
<http://llvm.org/releases/3.9.0/docs/ReleaseNotes.html>
<http://llvm.org/releases/3.9.0/tools/clang/docs/ReleaseNotes.html>
<http://llvm.org/releases/3.9.0/tools/lld/docs/ReleaseNotes.html>

Thanks to Ed Maste, Bryan Drewery, Andrew Turner, Antoine Brodin and Jan
Beich for their help.

Relnotes:	yes

MFC r309147:

Pull in r282174 from upstream llvm trunk (by Krzysztof Parzyszek):

  [PPC] Set SP after loading data from stack frame, if no red zone is
  present

  Follow-up to r280705: Make sure that the SP is only restored after
  all data is loaded from the stack frame, if there is no red zone.

  This completes the fix for
  https://llvm.org/bugs/show_bug.cgi?id=26519.

  Differential Revision: https://reviews.llvm.org/D24466

Reported by:    Mark Millard
PR:             214433

MFC r309149:

Pull in r283060 from upstream llvm trunk (by Hal Finkel):

  [PowerPC] Refactor soft-float support, and enable PPC64 soft float

  This change enables soft-float for PowerPC64, and also makes
  soft-float disable all vector instruction sets for both 32-bit and
  64-bit modes. This latter part is necessary because the PPC backend
  canonicalizes many Altivec vector types to floating-point types, and
  so soft-float breaks scalarization support for many operations. Both
  for embedded targets and for operating-system kernels desiring
  soft-float support, it seems reasonable that disabling hardware
  floating-point also disables vector instructions (embedded targets
  without hardware floating point support are unlikely to have Altivec,
  etc. and operating system kernels desiring not to use floating-point
  registers to lower syscall cost are unlikely to want to use vector
  registers either). If someone needs this to work, we'll need to
  change the fact that we promote many Altivec operations to act on
  v4f32. To make it possible to disable Altivec when soft-float is
  enabled, hardware floating-point support needs to be expressed as a
  positive feature, like the others, and not a negative feature,
  because target features cannot have dependencies on the disabling of
  some other feature. So +soft-float has now become -hard-float.

  Fixes PR26970.

Pull in r283061 from upstream clang trunk (by Hal Finkel):

  [PowerPC] Enable soft-float for PPC64, and +soft-float -> -hard-float

  Enable soft-float support on PPC64, as the backend now supports it.
  Also, the backend now uses -hard-float instead of +soft-float, so set
  the target features accordingly.

  Fixes PR26970.

Reported by:	Mark Millard
PR:		214433

MFC r309212:

Add a few missed clang 3.9.0 files to OptionalObsoleteFiles.

MFC r309262:

Fix packaging for clang, lldb and lld 3.9.0

During the upgrade of clang/llvm etc to 3.9.0 in r309124, the PACKAGE
directive in the usr.bin/clang/*.mk files got dropped accidentally.

Restore it, with a few minor changes and additions:
* Correct license in clang.ucl to NCSA
* Add PACKAGE=clang for clang and most of the "ll" tools
* Put lldb in its own package
* Put lld in its own package

Reviewed by:	gjb, jmallett
Differential Revision: https://reviews.freebsd.org/D8666

MFC r309656:

During the bootstrap phase, when building the minimal llvm library on
PowerPC, add lib/Support/Atomic.cpp.  This is needed because upstream
llvm revision r271821 disabled the use of std::call_once, which causes
some fallback functions from Atomic.cpp to be used instead.

Reported by:	Mark Millard
PR:		214902

MFC r309835:

Tentatively apply https://reviews.llvm.org/D18730 to work around gcc PR
70528 (bogus error: constructor required before non-static data member).
This should fix buildworld with the external gcc package.

Reported by:	https://jenkins.freebsd.org/job/FreeBSD_HEAD_amd64_gcc/

MFC r310194:

Upgrade our copies of clang, llvm, lld, lldb, compiler-rt and libc++ to
3.9.1 release.

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

Release notes for llvm, clang and lld will be available here:
<http://releases.llvm.org/3.9.1/docs/ReleaseNotes.html>
<http://releases.llvm.org/3.9.1/tools/clang/docs/ReleaseNotes.html>
<http://releases.llvm.org/3.9.1/tools/lld/docs/ReleaseNotes.html>

Relnotes:	yes

1 files changed, 159 insertions, 0 deletions

diff --git a/contrib/llvm/lib/Support/CachePruning.cpp b/contrib/llvm/lib/Support/CachePruning.cpp
new file mode 100644
index 0000000..bd42bef
--- /dev/null
+++ b/contrib/llvm/lib/Support/CachePruning.cpp
@@ -0,0 +1,159 @@
+//===-CachePruning.cpp - LLVM Cache Directory Pruning ---------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the pruning of a directory based on least recently used.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/CachePruning.h"
+
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/Errc.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/raw_ostream.h"
+
+#define DEBUG_TYPE "cache-pruning"
+
+#include <set>
+
+using namespace llvm;
+
+/// Write a new timestamp file with the given path. This is used for the pruning
+/// interval option.
+static void writeTimestampFile(StringRef TimestampFile) {
+  std::error_code EC;
+  raw_fd_ostream Out(TimestampFile.str(), EC, sys::fs::F_None);
+}
+
+/// Prune the cache of files that haven't been accessed in a long time.
+bool CachePruning::prune() {
+  if (Path.empty())
+    return false;
+
+  bool isPathDir;
+  if (sys::fs::is_directory(Path, isPathDir))
+    return false;
+
+  if (!isPathDir)
+    return false;
+
+  if (Expiration == 0 && PercentageOfAvailableSpace == 0) {
+    DEBUG(dbgs() << "No pruning settings set, exit early\n");
+    // Nothing will be pruned, early exit
+    return false;
+  }
+
+  // Try to stat() the timestamp file.
+  SmallString<128> TimestampFile(Path);
+  sys::path::append(TimestampFile, "llvmcache.timestamp");
+  sys::fs::file_status FileStatus;
+  sys::TimeValue CurrentTime = sys::TimeValue::now();
+  if (auto EC = sys::fs::status(TimestampFile, FileStatus)) {
+    if (EC == errc::no_such_file_or_directory) {
+      // If the timestamp file wasn't there, create one now.
+      writeTimestampFile(TimestampFile);
+    } else {
+      // Unknown error?
+      return false;
+    }
+  } else {
+    if (Interval) {
+      // Check whether the time stamp is older than our pruning interval.
+      // If not, do nothing.
+      sys::TimeValue TimeStampModTime = FileStatus.getLastModificationTime();
+      auto TimeInterval = sys::TimeValue(sys::TimeValue::SecondsType(Interval));
+      auto TimeStampAge = CurrentTime - TimeStampModTime;
+      if (TimeStampAge <= TimeInterval) {
+        DEBUG(dbgs() << "Timestamp file too recent (" << TimeStampAge.seconds()
+                     << "s old), do not prune.\n");
+        return false;
+      }
+    }
+    // Write a new timestamp file so that nobody else attempts to prune.
+    // There is a benign race condition here, if two processes happen to
+    // notice at the same time that the timestamp is out-of-date.
+    writeTimestampFile(TimestampFile);
+  }
+
+  bool ShouldComputeSize = (PercentageOfAvailableSpace > 0);
+
+  // Keep track of space
+  std::set<std::pair<uint64_t, std::string>> FileSizes;
+  uint64_t TotalSize = 0;
+  // Helper to add a path to the set of files to consider for size-based
+  // pruning, sorted by size.
+  auto AddToFileListForSizePruning =
+      [&](StringRef Path) {
+        if (!ShouldComputeSize)
+          return;
+        TotalSize += FileStatus.getSize();
+        FileSizes.insert(
+            std::make_pair(FileStatus.getSize(), std::string(Path)));
+      };
+
+  // Walk the entire directory cache, looking for unused files.
+  std::error_code EC;
+  SmallString<128> CachePathNative;
+  sys::path::native(Path, CachePathNative);
+  auto TimeExpiration = sys::TimeValue(sys::TimeValue::SecondsType(Expiration));
+  // Walk all of the files within this directory.
+  for (sys::fs::directory_iterator File(CachePathNative, EC), FileEnd;
+       File != FileEnd && !EC; File.increment(EC)) {
+    // Do not touch the timestamp.
+    if (File->path() == TimestampFile)
+      continue;
+
+    // Look at this file. If we can't stat it, there's nothing interesting
+    // there.
+    if (sys::fs::status(File->path(), FileStatus)) {
+      DEBUG(dbgs() << "Ignore " << File->path() << " (can't stat)\n");
+      continue;
+    }
+
+    // If the file hasn't been used recently enough, delete it
+    sys::TimeValue FileAccessTime = FileStatus.getLastAccessedTime();
+    auto FileAge = CurrentTime - FileAccessTime;
+    if (FileAge > TimeExpiration) {
+      DEBUG(dbgs() << "Remove " << File->path() << " (" << FileAge.seconds()
+                   << "s old)\n");
+      sys::fs::remove(File->path());
+      continue;
+    }
+
+    // Leave it here for now, but add it to the list of size-based pruning.
+    AddToFileListForSizePruning(File->path());
+  }
+
+  // Prune for size now if needed
+  if (ShouldComputeSize) {
+    auto ErrOrSpaceInfo = sys::fs::disk_space(Path);
+    if (!ErrOrSpaceInfo) {
+      report_fatal_error("Can't get available size");
+    }
+    sys::fs::space_info SpaceInfo = ErrOrSpaceInfo.get();
+    auto AvailableSpace = TotalSize + SpaceInfo.free;
+    auto FileAndSize = FileSizes.rbegin();
+    DEBUG(dbgs() << "Occupancy: " << ((100 * TotalSize) / AvailableSpace)
+                 << "% target is: " << PercentageOfAvailableSpace << "\n");
+    // Remove the oldest accessed files first, till we get below the threshold
+    while (((100 * TotalSize) / AvailableSpace) > PercentageOfAvailableSpace &&
+           FileAndSize != FileSizes.rend()) {
+      // Remove the file.
+      sys::fs::remove(FileAndSize->second);
+      // Update size
+      TotalSize -= FileAndSize->first;
+      DEBUG(dbgs() << " - Remove " << FileAndSize->second << " (size "
+                   << FileAndSize->first << "), new occupancy is " << TotalSize
+                   << "%\n");
+      ++FileAndSize;
+    }
+  }
+  return true;
+}