Merge llvm-project 12.0.1 release and follow-up fixes

Merge llvm-project main llvmorg-12-init-17869-g8e464dd76bef

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-12-init-17869-g8e464dd76bef, the last commit before the
upstream release/12.x branch was created.

PR:		255570

(cherry picked from commit e8d8bef961a50d4dc22501cde4fb9fb0be1b2532)

Merge llvm-project 12.0.0 release

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-12.0.0-0-gd28af7c654d8, a.k.a. 12.0.0 release.

PR:		255570

(cherry picked from commit d409305fa3838fb39b38c26fc085fb729b8766d5)

Disable strict-fp for powerpcspe, as it does not work properly yet

Merge commit 5c18d1136665 from llvm git (by Qiu Chaofan)

  [SPE] Disable strict-fp for SPE by default

  As discussed in PR50385, strict-fp on PowerPC SPE has not been
  handled well. This patch disables it by default for SPE.

  Reviewed By: nemanjai, vit9696, jhibbits

  Differential Revision: https://reviews.llvm.org/D103235

PR:		255570

(cherry picked from commit 715df83abc049b23d9acddc81f2480bd4c056d64)

Apply upstream libc++ fix to allow building with devel/xxx-xtoolchain-gcc

Merge commit 52e9d80d5db2 from llvm git (by Jason Liu):

  [libc++] add `inline` for __open's definition in ifstream and ofstream

  Summary:

  When building with gcc on AIX, it seems that gcc does not like the
  `always_inline` without the `inline` keyword.
  So adding the inline keywords in for __open in ifstream and ofstream.
  That will also make it consistent with __open in basic_filebuf
  (it seems we added `inline` there before for gcc build as well).

  Differential Revision: https://reviews.llvm.org/D99422

PR:		255570

(cherry picked from commit d099db25464b826c5724cf2fb5b22292bbe15f6e)

Undefine HAVE_(DE)REGISTER_FRAME in llvm's config.h on arm

Otherwise, the lli tool (enable by WITH_CLANG_EXTRAS) won't link on arm,
stating that __register_frame is undefined. This function is normally
provided by libunwind, but explicitly not for the ARM Exception ABI.

Reported by:	oh
PR:		255570

(cherry picked from commit f336b45e943c7f9a90ffcea1a6c4c7039e54c73c)

Merge llvm-project 12.0.1 rc2

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-12.0.1-rc2-0-ge7dac564cd0e, a.k.a. 12.0.1 rc2.

PR:		255570

(cherry picked from commit 23408297fbf3089f0388a8873b02fa75ab3f5bb9)

Revert libunwind change to fix backtrace segfault on aarch64

Revert commit 22b615a96593 from llvm git (by Daniel Kiss):

  [libunwind] Support for leaf function unwinding.

  Unwinding leaf function is useful in cases when the backtrace finds a
  leaf function for example when it caused a signal.
  This patch also add the support for the DW_CFA_undefined because it marks
  the end of the frames.

  Ryan Prichard provided code for the tests.

  Reviewed By: #libunwind, mstorsjo

  Differential Revision: https://reviews.llvm.org/D83573

  Reland with limit the test to the x86_64-linux target.

Bisection has shown that this particular upstream commit causes programs
using backtrace(3) on aarch64 to segfault. This affects the lang/rust
port, for instance. Until we can upstream to fix this problem, revert
the commit for now.

Reported by:	mikael
PR:		256864

(cherry picked from commit 5866c369e4fd917c0d456f0f10b92ee354b82279)

Merge llvm-project 12.0.1 release

This updates llvm, clang, compiler-rt, libc++, libunwind, lld, lldb and
openmp to llvmorg-12.0.1-0-gfed41342a82f, a.k.a. 12.0.1 release.

PR:		255570

(cherry picked from commit 4652422eb477731f284b1345afeefef7f269da50)

compilert-rt: build out-of-line LSE atomics helpers for aarch64

Both clang >= 12 and gcc >= 10.1 now default to -moutline-atomics for
aarch64. This requires a bunch of helper functions in libcompiler_rt.a,
to avoid link errors like "undefined symbol: __aarch64_ldadd8_acq_rel".

(Note: of course you can use -mno-outline-atomics as a workaround too,
but this would negate the potential performance benefit of the faster
LSE instructions.)

Bump __FreeBSD_version so ports maintainers can easily detect this.

PR:		257392

(cherry picked from commit cc55ee8009a550810d38777fd6ace9abf3a2f6b4)

1 files changed, 170 insertions, 10 deletions

diff --git a/contrib/llvm-project/llvm/lib/CodeGen/StackMaps.cpp b/contrib/llvm-project/llvm/lib/CodeGen/StackMaps.cpp
index 1e060ecbeb43..faf07e90c39c 100644
--- a/contrib/llvm-project/llvm/lib/CodeGen/StackMaps.cpp
+++ b/contrib/llvm-project/llvm/lib/CodeGen/StackMaps.cpp
@@ -45,6 +45,14 @@ static cl::opt<int> StackMapVersion(
 
 const char *StackMaps::WSMP = "Stack Maps: ";
 
+static uint64_t getConstMetaVal(const MachineInstr &MI, unsigned Idx) {
+  assert(MI.getOperand(Idx).isImm() &&
+         MI.getOperand(Idx).getImm() == StackMaps::ConstantOp);
+  const auto &MO = MI.getOperand(Idx + 1);
+  assert(MO.isImm());
+  return MO.getImm();
+}
+
 StackMapOpers::StackMapOpers(const MachineInstr *MI)
   : MI(MI) {
   assert(getVarIdx() <= MI->getNumOperands() &&
@@ -83,11 +91,89 @@ unsigned PatchPointOpers::getNextScratchIdx(unsigned StartIdx) const {
   return ScratchIdx;
 }
 
+unsigned StatepointOpers::getNumGcMapEntriesIdx() {
+  // Take index of num of allocas and skip all allocas records.
+  unsigned CurIdx = getNumAllocaIdx();
+  unsigned NumAllocas = getConstMetaVal(*MI, CurIdx - 1);
+  CurIdx++;
+  while (NumAllocas--)
+    CurIdx = StackMaps::getNextMetaArgIdx(MI, CurIdx);
+  return CurIdx + 1; // skip <StackMaps::ConstantOp>
+}
+
+unsigned StatepointOpers::getNumAllocaIdx() {
+  // Take index of num of gc ptrs and skip all gc ptr records.
+  unsigned CurIdx = getNumGCPtrIdx();
+  unsigned NumGCPtrs = getConstMetaVal(*MI, CurIdx - 1);
+  CurIdx++;
+  while (NumGCPtrs--)
+    CurIdx = StackMaps::getNextMetaArgIdx(MI, CurIdx);
+  return CurIdx + 1; // skip <StackMaps::ConstantOp>
+}
+
+unsigned StatepointOpers::getNumGCPtrIdx() {
+  // Take index of num of deopt args and skip all deopt records.
+  unsigned CurIdx = getNumDeoptArgsIdx();
+  unsigned NumDeoptArgs = getConstMetaVal(*MI, CurIdx - 1);
+  CurIdx++;
+  while (NumDeoptArgs--) {
+    CurIdx = StackMaps::getNextMetaArgIdx(MI, CurIdx);
+  }
+  return CurIdx + 1; // skip <StackMaps::ConstantOp>
+}
+
+int StatepointOpers::getFirstGCPtrIdx() {
+  unsigned NumGCPtrsIdx = getNumGCPtrIdx();
+  unsigned NumGCPtrs = getConstMetaVal(*MI, NumGCPtrsIdx - 1);
+  if (NumGCPtrs == 0)
+    return -1;
+  ++NumGCPtrsIdx; // skip <num gc ptrs>
+  assert(NumGCPtrsIdx < MI->getNumOperands());
+  return (int)NumGCPtrsIdx;
+}
+
+unsigned StatepointOpers::getGCPointerMap(
+    SmallVectorImpl<std::pair<unsigned, unsigned>> &GCMap) {
+  unsigned CurIdx = getNumGcMapEntriesIdx();
+  unsigned GCMapSize = getConstMetaVal(*MI, CurIdx - 1);
+  CurIdx++;
+  for (unsigned N = 0; N < GCMapSize; ++N) {
+    unsigned B = MI->getOperand(CurIdx++).getImm();
+    unsigned D = MI->getOperand(CurIdx++).getImm();
+    GCMap.push_back(std::make_pair(B, D));
+  }
+
+  return GCMapSize;
+}
+
 StackMaps::StackMaps(AsmPrinter &AP) : AP(AP) {
   if (StackMapVersion != 3)
     llvm_unreachable("Unsupported stackmap version!");
 }
 
+unsigned StackMaps::getNextMetaArgIdx(const MachineInstr *MI, unsigned CurIdx) {
+  assert(CurIdx < MI->getNumOperands() && "Bad meta arg index");
+  const auto &MO = MI->getOperand(CurIdx);
+  if (MO.isImm()) {
+    switch (MO.getImm()) {
+    default:
+      llvm_unreachable("Unrecognized operand type.");
+    case StackMaps::DirectMemRefOp:
+      CurIdx += 2;
+      break;
+    case StackMaps::IndirectMemRefOp:
+      CurIdx += 3;
+      break;
+    case StackMaps::ConstantOp:
+      ++CurIdx;
+      break;
+    }
+  }
+  ++CurIdx;
+  assert(CurIdx < MI->getNumOperands() && "points past operand list");
+  return CurIdx;
+}
+
 /// Go up the super-register chain until we hit a valid dwarf register number.
 static unsigned getDwarfRegNum(unsigned Reg, const TargetRegisterInfo *TRI) {
   int RegNum = TRI->getDwarfRegNum(Reg, false);
@@ -148,6 +234,12 @@ StackMaps::parseOperand(MachineInstr::const_mop_iterator MOI,
     if (MOI->isImplicit())
       return ++MOI;
 
+    if (MOI->isUndef()) {
+      // Record `undef` register as constant. Use same value as ISel uses.
+      Locs.emplace_back(Location::Constant, sizeof(int64_t), 0, 0xFEFEFEFE);
+      return ++MOI;
+    }
+
     assert(Register::isPhysicalRegister(MOI->getReg()) &&
            "Virtreg operands should have been rewritten before now.");
     const TargetRegisterClass *RC = TRI->getMinimalPhysRegClass(MOI->getReg());
@@ -286,14 +378,82 @@ StackMaps::parseRegisterLiveOutMask(const uint32_t *Mask) const {
     }
   }
 
-  LiveOuts.erase(
-      llvm::remove_if(LiveOuts,
-                      [](const LiveOutReg &LO) { return LO.Reg == 0; }),
-      LiveOuts.end());
+  llvm::erase_if(LiveOuts, [](const LiveOutReg &LO) { return LO.Reg == 0; });
 
   return LiveOuts;
 }
 
+// See statepoint MI format description in StatepointOpers' class comment
+// in include/llvm/CodeGen/StackMaps.h
+void StackMaps::parseStatepointOpers(const MachineInstr &MI,
+                                     MachineInstr::const_mop_iterator MOI,
+                                     MachineInstr::const_mop_iterator MOE,
+                                     LocationVec &Locations,
+                                     LiveOutVec &LiveOuts) {
+  LLVM_DEBUG(dbgs() << "record statepoint : " << MI << "\n");
+  StatepointOpers SO(&MI);
+  MOI = parseOperand(MOI, MOE, Locations, LiveOuts); // CC
+  MOI = parseOperand(MOI, MOE, Locations, LiveOuts); // Flags
+  MOI = parseOperand(MOI, MOE, Locations, LiveOuts); // Num Deopts
+
+  // Record Deopt Args.
+  unsigned NumDeoptArgs = Locations.back().Offset;
+  assert(Locations.back().Type == Location::Constant);
+  assert(NumDeoptArgs == SO.getNumDeoptArgs());
+
+  while (NumDeoptArgs--)
+    MOI = parseOperand(MOI, MOE, Locations, LiveOuts);
+
+  // Record gc base/derived pairs
+  assert(MOI->isImm() && MOI->getImm() == StackMaps::ConstantOp);
+  ++MOI;
+  assert(MOI->isImm());
+  unsigned NumGCPointers = MOI->getImm();
+  ++MOI;
+  if (NumGCPointers) {
+    // Map logical index of GC ptr to MI operand index.
+    SmallVector<unsigned, 8> GCPtrIndices;
+    unsigned GCPtrIdx = (unsigned)SO.getFirstGCPtrIdx();
+    assert((int)GCPtrIdx != -1);
+    assert(MOI - MI.operands_begin() == GCPtrIdx + 0LL);
+    while (NumGCPointers--) {
+      GCPtrIndices.push_back(GCPtrIdx);
+      GCPtrIdx = StackMaps::getNextMetaArgIdx(&MI, GCPtrIdx);
+    }
+
+    SmallVector<std::pair<unsigned, unsigned>, 8> GCPairs;
+    unsigned NumGCPairs = SO.getGCPointerMap(GCPairs);
+    (void)NumGCPairs;
+    LLVM_DEBUG(dbgs() << "NumGCPairs = " << NumGCPairs << "\n");
+
+    auto MOB = MI.operands_begin();
+    for (auto &P : GCPairs) {
+      assert(P.first < GCPtrIndices.size() && "base pointer index not found");
+      assert(P.second < GCPtrIndices.size() &&
+             "derived pointer index not found");
+      unsigned BaseIdx = GCPtrIndices[P.first];
+      unsigned DerivedIdx = GCPtrIndices[P.second];
+      LLVM_DEBUG(dbgs() << "Base : " << BaseIdx << " Derived : " << DerivedIdx
+                        << "\n");
+      (void)parseOperand(MOB + BaseIdx, MOE, Locations, LiveOuts);
+      (void)parseOperand(MOB + DerivedIdx, MOE, Locations, LiveOuts);
+    }
+
+    MOI = MOB + GCPtrIdx;
+  }
+
+  // Record gc allocas
+  assert(MOI < MOE);
+  assert(MOI->isImm() && MOI->getImm() == StackMaps::ConstantOp);
+  ++MOI;
+  unsigned NumAllocas = MOI->getImm();
+  ++MOI;
+  while (NumAllocas--) {
+    MOI = parseOperand(MOI, MOE, Locations, LiveOuts);
+    assert(MOI < MOE);
+  }
+}
+
 void StackMaps::recordStackMapOpers(const MCSymbol &MILabel,
                                     const MachineInstr &MI, uint64_t ID,
                                     MachineInstr::const_mop_iterator MOI,
@@ -311,9 +471,11 @@ void StackMaps::recordStackMapOpers(const MCSymbol &MILabel,
   }
 
   // Parse operands.
-  while (MOI != MOE) {
-    MOI = parseOperand(MOI, MOE, Locations, LiveOuts);
-  }
+  if (MI.getOpcode() == TargetOpcode::STATEPOINT)
+    parseStatepointOpers(MI, MOI, MOE, Locations, LiveOuts);
+  else
+    while (MOI != MOE)
+      MOI = parseOperand(MOI, MOE, Locations, LiveOuts);
 
   // Move large constants into the constant pool.
   for (auto &Loc : Locations) {
@@ -394,8 +556,6 @@ void StackMaps::recordStatepoint(const MCSymbol &L, const MachineInstr &MI) {
   assert(MI.getOpcode() == TargetOpcode::STATEPOINT && "expected statepoint");
 
   StatepointOpers opers(&MI);
-  // Record all the deopt and gc operands (they're contiguous and run from the
-  // initial index to the end of the operand list)
   const unsigned StartIdx = opers.getVarIdx();
   recordStackMapOpers(L, MI, opers.getID(), MI.operands_begin() + StartIdx,
                       MI.operands_end(), false);
@@ -404,7 +564,7 @@ void StackMaps::recordStatepoint(const MCSymbol &L, const MachineInstr &MI) {
 /// Emit the stackmap header.
 ///
 /// Header {
-///   uint8  : Stack Map Version (currently 2)
+///   uint8  : Stack Map Version (currently 3)
 ///   uint8  : Reserved (expected to be 0)
 ///   uint16 : Reserved (expected to be 0)
 /// }