MFC 261991:

Upgrade our copy of llvm/clang to 3.4 release.  This version supports
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 262121 (by emaste):

Update lldb for clang/llvm 3.4 import

This commit largely restores the lldb source to the upstream r196259
snapshot with the addition of threaded inferior support and a few bug
fixes.

Specific upstream lldb revisions restored include:
   SVN      git
  181387  779e6ac
  181703  7bef4e2
  182099  b31044e
  182650  f2dcf35
  182683  0d91b80
  183862  15c1774
  183929  99447a6
  184177  0b2934b
  184948  4dc3761
  184954  007e7bc
  186990  eebd175

Sponsored by:	DARPA, AFRL

MFC 262186 (by emaste):

Fix mismerge in r262121

A break statement was lost in the merge.  The error had no functional
impact, but restore it to reduce the diff against upstream.

MFC 262303:

Pull in r197521 from upstream clang trunk (by rdivacky):

  Use the integrated assembler by default on FreeBSD/ppc and ppc64.

Requested by:	jhibbits

MFC 262611:

Pull in r196874 from upstream llvm trunk:

  Fix a crash that occurs when PWD is invalid.

  MCJIT needs to be able to run in hostile environments, even when PWD
  is invalid. There's no need to crash MCJIT in this case.

  The obvious fix is to simply leave MCContext's CompilationDir empty
  when PWD can't be determined. This way, MCJIT clients,
  and other clients that link with LLVM don't need a valid working directory.

  If we do want to guarantee valid CompilationDir, that should be done
  only for clients of getCompilationDir(). This is as simple as checking
  for an empty string.

  The only current use of getCompilationDir is EmitGenDwarfInfo, which
  won't conceivably run with an invalid working dir. However, in the
  purely hypothetically and untestable case that this happens, the
  AT_comp_dir will be omitted from the compilation_unit DIE.

This should help fix assertions occurring with ports-mgmt/tinderbox,
when it is using jails, and sometimes invalidates clang's current
working directory.

Reported by:	decke

MFC 262809:

Pull in r203007 from upstream clang trunk:

  Don't produce an alias between destructors with different calling conventions.

  Fixes pr19007.

(Please note that is an LLVM PR identifier, not a FreeBSD one.)

This should fix Firefox and/or libxul crashes (due to problems with
regparm/stdcall calling conventions) on i386.

Reported by:	multiple users on freebsd-current
PR:		bin/187103

MFC 263048:

Repair recognition of "CC" as an alias for the C++ compiler, since it
was silently broken by upstream for a Windows-specific use-case.

Apparently some versions of CMake still rely on this archaic feature...

Reported by:	rakuco

MFC 263049:

Garbage collect the old way of adding the libstdc++ include directories
in clang's InitHeaderSearch.cpp.  This has been superseded by David
Chisnall's commit in r255321.

Moreover, if libc++ is used, the libstdc++ include directories should
not be in the search path at all.  These directories are now only used
if you pass -stdlib=libstdc++.

1 files changed, 293 insertions, 0 deletions

diff --git a/contrib/llvm/lib/Target/SystemZ/SystemZSelectionDAGInfo.cpp b/contrib/llvm/lib/Target/SystemZ/SystemZSelectionDAGInfo.cpp
new file mode 100644
index 0000000..c7ebb5d
--- /dev/null
+++ b/contrib/llvm/lib/Target/SystemZ/SystemZSelectionDAGInfo.cpp
@@ -0,0 +1,293 @@
+//===-- SystemZSelectionDAGInfo.cpp - SystemZ SelectionDAG Info -----------===//
+//
+//                     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 SystemZSelectionDAGInfo class.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "systemz-selectiondag-info"
+#include "SystemZTargetMachine.h"
+#include "llvm/CodeGen/SelectionDAG.h"
+
+using namespace llvm;
+
+SystemZSelectionDAGInfo::
+SystemZSelectionDAGInfo(const SystemZTargetMachine &TM)
+  : TargetSelectionDAGInfo(TM) {
+}
+
+SystemZSelectionDAGInfo::~SystemZSelectionDAGInfo() {
+}
+
+// Decide whether it is best to use a loop or straight-line code for
+// a block operation of Size bytes with source address Src and destination
+// address Dest.  Sequence is the opcode to use for straight-line code
+// (such as MVC) and Loop is the opcode to use for loops (such as MVC_LOOP).
+// Return the chain for the completed operation.
+static SDValue emitMemMem(SelectionDAG &DAG, SDLoc DL, unsigned Sequence,
+                          unsigned Loop, SDValue Chain, SDValue Dst,
+                          SDValue Src, uint64_t Size) {
+  EVT PtrVT = Src.getValueType();
+  // The heuristic we use is to prefer loops for anything that would
+  // require 7 or more MVCs.  With these kinds of sizes there isn't
+  // much to choose between straight-line code and looping code,
+  // since the time will be dominated by the MVCs themselves.
+  // However, the loop has 4 or 5 instructions (depending on whether
+  // the base addresses can be proved equal), so there doesn't seem
+  // much point using a loop for 5 * 256 bytes or fewer.  Anything in
+  // the range (5 * 256, 6 * 256) will need another instruction after
+  // the loop, so it doesn't seem worth using a loop then either.
+  // The next value up, 6 * 256, can be implemented in the same
+  // number of straight-line MVCs as 6 * 256 - 1.
+  if (Size > 6 * 256)
+    return DAG.getNode(Loop, DL, MVT::Other, Chain, Dst, Src,
+                       DAG.getConstant(Size, PtrVT),
+                       DAG.getConstant(Size / 256, PtrVT));
+  return DAG.getNode(Sequence, DL, MVT::Other, Chain, Dst, Src,
+                     DAG.getConstant(Size, PtrVT));
+}
+
+SDValue SystemZSelectionDAGInfo::
+EmitTargetCodeForMemcpy(SelectionDAG &DAG, SDLoc DL, SDValue Chain,
+                        SDValue Dst, SDValue Src, SDValue Size, unsigned Align,
+                        bool IsVolatile, bool AlwaysInline,
+                        MachinePointerInfo DstPtrInfo,
+                        MachinePointerInfo SrcPtrInfo) const {
+  if (IsVolatile)
+    return SDValue();
+
+  if (ConstantSDNode *CSize = dyn_cast<ConstantSDNode>(Size))
+    return emitMemMem(DAG, DL, SystemZISD::MVC, SystemZISD::MVC_LOOP,
+                      Chain, Dst, Src, CSize->getZExtValue());
+  return SDValue();
+}
+
+// Handle a memset of 1, 2, 4 or 8 bytes with the operands given by
+// Chain, Dst, ByteVal and Size.  These cases are expected to use
+// MVI, MVHHI, MVHI and MVGHI respectively.
+static SDValue memsetStore(SelectionDAG &DAG, SDLoc DL, SDValue Chain,
+                           SDValue Dst, uint64_t ByteVal, uint64_t Size,
+                           unsigned Align,
+                           MachinePointerInfo DstPtrInfo) {
+  uint64_t StoreVal = ByteVal;
+  for (unsigned I = 1; I < Size; ++I)
+    StoreVal |= ByteVal << (I * 8);
+  return DAG.getStore(Chain, DL,
+                      DAG.getConstant(StoreVal, MVT::getIntegerVT(Size * 8)),
+                      Dst, DstPtrInfo, false, false, Align);
+}
+
+SDValue SystemZSelectionDAGInfo::
+EmitTargetCodeForMemset(SelectionDAG &DAG, SDLoc DL, SDValue Chain,
+                        SDValue Dst, SDValue Byte, SDValue Size,
+                        unsigned Align, bool IsVolatile,
+                        MachinePointerInfo DstPtrInfo) const {
+  EVT PtrVT = Dst.getValueType();
+
+  if (IsVolatile)
+    return SDValue();
+
+  if (ConstantSDNode *CSize = dyn_cast<ConstantSDNode>(Size)) {
+    uint64_t Bytes = CSize->getZExtValue();
+    if (Bytes == 0)
+      return SDValue();
+    if (ConstantSDNode *CByte = dyn_cast<ConstantSDNode>(Byte)) {
+      // Handle cases that can be done using at most two of
+      // MVI, MVHI, MVHHI and MVGHI.  The latter two can only be
+      // used if ByteVal is all zeros or all ones; in other casees,
+      // we can move at most 2 halfwords.
+      uint64_t ByteVal = CByte->getZExtValue();
+      if (ByteVal == 0 || ByteVal == 255 ?
+          Bytes <= 16 && CountPopulation_64(Bytes) <= 2 :
+          Bytes <= 4) {
+        unsigned Size1 = Bytes == 16 ? 8 : 1 << findLastSet(Bytes);
+        unsigned Size2 = Bytes - Size1;
+        SDValue Chain1 = memsetStore(DAG, DL, Chain, Dst, ByteVal, Size1,
+                                     Align, DstPtrInfo);
+        if (Size2 == 0)
+          return Chain1;
+        Dst = DAG.getNode(ISD::ADD, DL, PtrVT, Dst,
+                          DAG.getConstant(Size1, PtrVT));
+        DstPtrInfo = DstPtrInfo.getWithOffset(Size1);
+        SDValue Chain2 = memsetStore(DAG, DL, Chain, Dst, ByteVal, Size2,
+                                     std::min(Align, Size1), DstPtrInfo);
+        return DAG.getNode(ISD::TokenFactor, DL, MVT::Other, Chain1, Chain2);
+      }
+    } else {
+      // Handle one and two bytes using STC.
+      if (Bytes <= 2) {
+        SDValue Chain1 = DAG.getStore(Chain, DL, Byte, Dst, DstPtrInfo,
+                                      false, false, Align);
+        if (Bytes == 1)
+          return Chain1;
+        SDValue Dst2 = DAG.getNode(ISD::ADD, DL, PtrVT, Dst,
+                                   DAG.getConstant(1, PtrVT));
+        SDValue Chain2 = DAG.getStore(Chain, DL, Byte, Dst2,
+                                      DstPtrInfo.getWithOffset(1),
+                                      false, false, 1);
+        return DAG.getNode(ISD::TokenFactor, DL, MVT::Other, Chain1, Chain2);
+      }
+    }
+    assert(Bytes >= 2 && "Should have dealt with 0- and 1-byte cases already");
+
+    // Handle the special case of a memset of 0, which can use XC.
+    ConstantSDNode *CByte = dyn_cast<ConstantSDNode>(Byte);
+    if (CByte && CByte->getZExtValue() == 0)
+      return emitMemMem(DAG, DL, SystemZISD::XC, SystemZISD::XC_LOOP,
+                        Chain, Dst, Dst, Bytes);
+
+    // Copy the byte to the first location and then use MVC to copy
+    // it to the rest.
+    Chain = DAG.getStore(Chain, DL, Byte, Dst, DstPtrInfo,
+                         false, false, Align);
+    SDValue DstPlus1 = DAG.getNode(ISD::ADD, DL, PtrVT, Dst,
+                                   DAG.getConstant(1, PtrVT));
+    return emitMemMem(DAG, DL, SystemZISD::MVC, SystemZISD::MVC_LOOP,
+                      Chain, DstPlus1, Dst, Bytes - 1);
+  }
+  return SDValue();
+}
+
+// Use CLC to compare [Src1, Src1 + Size) with [Src2, Src2 + Size),
+// deciding whether to use a loop or straight-line code.
+static SDValue emitCLC(SelectionDAG &DAG, SDLoc DL, SDValue Chain,
+                       SDValue Src1, SDValue Src2, uint64_t Size) {
+  SDVTList VTs = DAG.getVTList(MVT::Other, MVT::Glue);
+  EVT PtrVT = Src1.getValueType();
+  // A two-CLC sequence is a clear win over a loop, not least because it
+  // needs only one branch.  A three-CLC sequence needs the same number
+  // of branches as a loop (i.e. 2), but is shorter.  That brings us to
+  // lengths greater than 768 bytes.  It seems relatively likely that
+  // a difference will be found within the first 768 bytes, so we just
+  // optimize for the smallest number of branch instructions, in order
+  // to avoid polluting the prediction buffer too much.  A loop only ever
+  // needs 2 branches, whereas a straight-line sequence would need 3 or more.
+  if (Size > 3 * 256)
+    return DAG.getNode(SystemZISD::CLC_LOOP, DL, VTs, Chain, Src1, Src2,
+                       DAG.getConstant(Size, PtrVT),
+                       DAG.getConstant(Size / 256, PtrVT));
+  return DAG.getNode(SystemZISD::CLC, DL, VTs, Chain, Src1, Src2,
+                     DAG.getConstant(Size, PtrVT));
+}
+
+// Convert the current CC value into an integer that is 0 if CC == 0,
+// less than zero if CC == 1 and greater than zero if CC >= 2.
+// The sequence starts with IPM, which puts CC into bits 29 and 28
+// of an integer and clears bits 30 and 31.
+static SDValue addIPMSequence(SDLoc DL, SDValue Glue, SelectionDAG &DAG) {
+  SDValue IPM = DAG.getNode(SystemZISD::IPM, DL, MVT::i32, Glue);
+  SDValue SRL = DAG.getNode(ISD::SRL, DL, MVT::i32, IPM,
+                            DAG.getConstant(SystemZ::IPM_CC, MVT::i32));
+  SDValue ROTL = DAG.getNode(ISD::ROTL, DL, MVT::i32, SRL,
+                             DAG.getConstant(31, MVT::i32));
+  return ROTL;
+}
+
+std::pair<SDValue, SDValue> SystemZSelectionDAGInfo::
+EmitTargetCodeForMemcmp(SelectionDAG &DAG, SDLoc DL, SDValue Chain,
+                        SDValue Src1, SDValue Src2, SDValue Size,
+                        MachinePointerInfo Op1PtrInfo,
+                        MachinePointerInfo Op2PtrInfo) const {
+  if (ConstantSDNode *CSize = dyn_cast<ConstantSDNode>(Size)) {
+    uint64_t Bytes = CSize->getZExtValue();
+    assert(Bytes > 0 && "Caller should have handled 0-size case");
+    Chain = emitCLC(DAG, DL, Chain, Src1, Src2, Bytes);
+    SDValue Glue = Chain.getValue(1);
+    return std::make_pair(addIPMSequence(DL, Glue, DAG), Chain);
+  }
+  return std::make_pair(SDValue(), SDValue());
+}
+
+std::pair<SDValue, SDValue> SystemZSelectionDAGInfo::
+EmitTargetCodeForMemchr(SelectionDAG &DAG, SDLoc DL, SDValue Chain,
+                        SDValue Src, SDValue Char, SDValue Length,
+                        MachinePointerInfo SrcPtrInfo) const {
+  // Use SRST to find the character.  End is its address on success.
+  EVT PtrVT = Src.getValueType();
+  SDVTList VTs = DAG.getVTList(PtrVT, MVT::Other, MVT::Glue);
+  Length = DAG.getZExtOrTrunc(Length, DL, PtrVT);
+  Char = DAG.getZExtOrTrunc(Char, DL, MVT::i32);
+  Char = DAG.getNode(ISD::AND, DL, MVT::i32, Char,
+                     DAG.getConstant(255, MVT::i32));
+  SDValue Limit = DAG.getNode(ISD::ADD, DL, PtrVT, Src, Length);
+  SDValue End = DAG.getNode(SystemZISD::SEARCH_STRING, DL, VTs, Chain,
+                            Limit, Src, Char);
+  Chain = End.getValue(1);
+  SDValue Glue = End.getValue(2);
+
+  // Now select between End and null, depending on whether the character
+  // was found.
+  SmallVector<SDValue, 5> Ops;
+  Ops.push_back(End);
+  Ops.push_back(DAG.getConstant(0, PtrVT));
+  Ops.push_back(DAG.getConstant(SystemZ::CCMASK_SRST, MVT::i32));
+  Ops.push_back(DAG.getConstant(SystemZ::CCMASK_SRST_FOUND, MVT::i32));
+  Ops.push_back(Glue);
+  VTs = DAG.getVTList(PtrVT, MVT::Glue);
+  End = DAG.getNode(SystemZISD::SELECT_CCMASK, DL, VTs, &Ops[0], Ops.size());
+  return std::make_pair(End, Chain);
+}
+
+std::pair<SDValue, SDValue> SystemZSelectionDAGInfo::
+EmitTargetCodeForStrcpy(SelectionDAG &DAG, SDLoc DL, SDValue Chain,
+                        SDValue Dest, SDValue Src,
+                        MachinePointerInfo DestPtrInfo,
+                        MachinePointerInfo SrcPtrInfo, bool isStpcpy) const {
+  SDVTList VTs = DAG.getVTList(Dest.getValueType(), MVT::Other);
+  SDValue EndDest = DAG.getNode(SystemZISD::STPCPY, DL, VTs, Chain, Dest, Src,
+                                DAG.getConstant(0, MVT::i32));
+  return std::make_pair(isStpcpy ? EndDest : Dest, EndDest.getValue(1));
+}
+
+std::pair<SDValue, SDValue> SystemZSelectionDAGInfo::
+EmitTargetCodeForStrcmp(SelectionDAG &DAG, SDLoc DL, SDValue Chain,
+                        SDValue Src1, SDValue Src2,
+                        MachinePointerInfo Op1PtrInfo,
+                        MachinePointerInfo Op2PtrInfo) const {
+  SDVTList VTs = DAG.getVTList(Src1.getValueType(), MVT::Other, MVT::Glue);
+  SDValue Unused = DAG.getNode(SystemZISD::STRCMP, DL, VTs, Chain, Src1, Src2,
+                               DAG.getConstant(0, MVT::i32));
+  Chain = Unused.getValue(1);
+  SDValue Glue = Chain.getValue(2);
+  return std::make_pair(addIPMSequence(DL, Glue, DAG), Chain);
+}
+
+// Search from Src for a null character, stopping once Src reaches Limit.
+// Return a pair of values, the first being the number of nonnull characters
+// and the second being the out chain.
+//
+// This can be used for strlen by setting Limit to 0.
+static std::pair<SDValue, SDValue> getBoundedStrlen(SelectionDAG &DAG, SDLoc DL,
+                                                    SDValue Chain, SDValue Src,
+                                                    SDValue Limit) {
+  EVT PtrVT = Src.getValueType();
+  SDVTList VTs = DAG.getVTList(PtrVT, MVT::Other, MVT::Glue);
+  SDValue End = DAG.getNode(SystemZISD::SEARCH_STRING, DL, VTs, Chain,
+                            Limit, Src, DAG.getConstant(0, MVT::i32));
+  Chain = End.getValue(1);
+  SDValue Len = DAG.getNode(ISD::SUB, DL, PtrVT, End, Src);
+  return std::make_pair(Len, Chain);
+}    
+
+std::pair<SDValue, SDValue> SystemZSelectionDAGInfo::
+EmitTargetCodeForStrlen(SelectionDAG &DAG, SDLoc DL, SDValue Chain,
+                        SDValue Src, MachinePointerInfo SrcPtrInfo) const {
+  EVT PtrVT = Src.getValueType();
+  return getBoundedStrlen(DAG, DL, Chain, Src, DAG.getConstant(0, PtrVT));
+}
+
+std::pair<SDValue, SDValue> SystemZSelectionDAGInfo::
+EmitTargetCodeForStrnlen(SelectionDAG &DAG, SDLoc DL, SDValue Chain,
+                         SDValue Src, SDValue MaxLength,
+                         MachinePointerInfo SrcPtrInfo) const {
+  EVT PtrVT = Src.getValueType();
+  MaxLength = DAG.getZExtOrTrunc(MaxLength, DL, PtrVT);
+  SDValue Limit = DAG.getNode(ISD::ADD, DL, PtrVT, Src, MaxLength);
+  return getBoundedStrlen(DAG, DL, Chain, Src, Limit);
+}