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, 213 insertions, 0 deletions

diff --git a/contrib/llvm-project/llvm/lib/MC/MCPseudoProbe.cpp b/contrib/llvm-project/llvm/lib/MC/MCPseudoProbe.cpp
new file mode 100644
index 000000000000..731831d3bce3
--- /dev/null
+++ b/contrib/llvm-project/llvm/lib/MC/MCPseudoProbe.cpp
@@ -0,0 +1,213 @@
+//===- lib/MC/MCPseudoProbe.cpp - Pseudo probe encoding support ----------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/MC/MCPseudoProbe.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCObjectFileInfo.h"
+#include "llvm/MC/MCObjectStreamer.h"
+#include "llvm/MC/MCStreamer.h"
+
+#define DEBUG_TYPE "mcpseudoprobe"
+
+using namespace llvm;
+
+#ifndef NDEBUG
+int MCPseudoProbeTable::DdgPrintIndent = 0;
+#endif
+
+static const MCExpr *buildSymbolDiff(MCObjectStreamer *MCOS, const MCSymbol *A,
+                                     const MCSymbol *B) {
+  MCContext &Context = MCOS->getContext();
+  MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;
+  const MCExpr *ARef = MCSymbolRefExpr::create(A, Variant, Context);
+  const MCExpr *BRef = MCSymbolRefExpr::create(B, Variant, Context);
+  const MCExpr *AddrDelta =
+      MCBinaryExpr::create(MCBinaryExpr::Sub, ARef, BRef, Context);
+  return AddrDelta;
+}
+
+void MCPseudoProbe::emit(MCObjectStreamer *MCOS,
+                         const MCPseudoProbe *LastProbe) const {
+  // Emit Index
+  MCOS->emitULEB128IntValue(Index);
+  // Emit Type and the flag:
+  // Type (bit 0 to 3), with bit 4 to 6 for attributes.
+  // Flag (bit 7, 0 - code address, 1 - address delta). This indicates whether
+  // the following field is a symbolic code address or an address delta.
+  assert(Type <= 0xF && "Probe type too big to encode, exceeding 15");
+  assert(Attributes <= 0x7 &&
+         "Probe attributes too big to encode, exceeding 7");
+  uint8_t PackedType = Type | (Attributes << 4);
+  uint8_t Flag = LastProbe ? ((int8_t)MCPseudoProbeFlag::AddressDelta << 7) : 0;
+  MCOS->emitInt8(Flag | PackedType);
+
+  if (LastProbe) {
+    // Emit the delta between the address label and LastProbe.
+    const MCExpr *AddrDelta =
+        buildSymbolDiff(MCOS, Label, LastProbe->getLabel());
+    int64_t Delta;
+    if (AddrDelta->evaluateAsAbsolute(Delta, MCOS->getAssemblerPtr())) {
+      MCOS->emitSLEB128IntValue(Delta);
+    } else {
+      MCOS->insert(new MCPseudoProbeAddrFragment(AddrDelta));
+    }
+  } else {
+    // Emit label as a symbolic code address.
+    MCOS->emitSymbolValue(
+        Label, MCOS->getContext().getAsmInfo()->getCodePointerSize());
+  }
+
+  LLVM_DEBUG({
+    dbgs().indent(MCPseudoProbeTable::DdgPrintIndent);
+    dbgs() << "Probe: " << Index << "\n";
+  });
+}
+
+MCPseudoProbeInlineTree::~MCPseudoProbeInlineTree() {
+  for (auto &Inlinee : Inlinees)
+    delete Inlinee.second;
+}
+
+MCPseudoProbeInlineTree *
+MCPseudoProbeInlineTree::getOrAddNode(InlineSite Site) {
+  auto Iter = Inlinees.find(Site);
+  if (Iter == Inlinees.end()) {
+    auto *Node = new MCPseudoProbeInlineTree(std::get<0>(Site));
+    Inlinees[Site] = Node;
+    return Node;
+  } else {
+    return Iter->second;
+  }
+}
+
+void MCPseudoProbeInlineTree::addPseudoProbe(
+    const MCPseudoProbe &Probe, const MCPseudoProbeInlineStack &InlineStack) {
+  // The function should not be called on the root.
+  assert(isRoot() && "Should not be called on root");
+
+  // When it comes here, the input look like:
+  //    Probe: GUID of C, ...
+  //    InlineStack: [88, A], [66, B]
+  // which means, Function A inlines function B at call site with a probe id of
+  // 88, and B inlines C at probe 66. The tri-tree expects a tree path like {[0,
+  // A], [88, B], [66, C]} to locate the tree node where the probe should be
+  // added. Note that the edge [0, A] means A is the top-level function we are
+  // emitting probes for.
+
+  // Make a [0, A] edge.
+  // An empty inline stack means the function that the probe originates from
+  // is a top-level function.
+  InlineSite Top;
+  if (InlineStack.empty()) {
+    Top = InlineSite(Probe.getGuid(), 0);
+  } else {
+    Top = InlineSite(std::get<0>(InlineStack.front()), 0);
+  }
+
+  auto *Cur = getOrAddNode(Top);
+
+  // Make interior edges by walking the inline stack. Once it's done, Cur should
+  // point to the node that the probe originates from.
+  if (!InlineStack.empty()) {
+    auto Iter = InlineStack.begin();
+    auto Index = std::get<1>(*Iter);
+    Iter++;
+    for (; Iter != InlineStack.end(); Iter++) {
+      // Make an edge by using the previous probe id and current GUID.
+      Cur = Cur->getOrAddNode(InlineSite(std::get<0>(*Iter), Index));
+      Index = std::get<1>(*Iter);
+    }
+    Cur = Cur->getOrAddNode(InlineSite(Probe.getGuid(), Index));
+  }
+
+  Cur->Probes.push_back(Probe);
+}
+
+void MCPseudoProbeInlineTree::emit(MCObjectStreamer *MCOS,
+                                   const MCPseudoProbe *&LastProbe) {
+  LLVM_DEBUG({
+    dbgs().indent(MCPseudoProbeTable::DdgPrintIndent);
+    dbgs() << "Group [\n";
+    MCPseudoProbeTable::DdgPrintIndent += 2;
+  });
+  // Emit probes grouped by GUID.
+  if (Guid != 0) {
+    LLVM_DEBUG({
+      dbgs().indent(MCPseudoProbeTable::DdgPrintIndent);
+      dbgs() << "GUID: " << Guid << "\n";
+    });
+    // Emit Guid
+    MCOS->emitInt64(Guid);
+    // Emit number of probes in this node
+    MCOS->emitULEB128IntValue(Probes.size());
+    // Emit number of direct inlinees
+    MCOS->emitULEB128IntValue(Inlinees.size());
+    // Emit probes in this group
+    for (const auto &Probe : Probes) {
+      Probe.emit(MCOS, LastProbe);
+      LastProbe = &Probe;
+    }
+  } else {
+    assert(Probes.empty() && "Root should not have probes");
+  }
+
+  // Emit descendent
+  for (const auto &Inlinee : Inlinees) {
+    if (Guid) {
+      // Emit probe index
+      MCOS->emitULEB128IntValue(std::get<1>(Inlinee.first));
+      LLVM_DEBUG({
+        dbgs().indent(MCPseudoProbeTable::DdgPrintIndent);
+        dbgs() << "InlineSite: " << std::get<1>(Inlinee.first) << "\n";
+      });
+    }
+    // Emit the group
+    Inlinee.second->emit(MCOS, LastProbe);
+  }
+
+  LLVM_DEBUG({
+    MCPseudoProbeTable::DdgPrintIndent -= 2;
+    dbgs().indent(MCPseudoProbeTable::DdgPrintIndent);
+    dbgs() << "]\n";
+  });
+}
+
+void MCPseudoProbeSection::emit(MCObjectStreamer *MCOS) {
+  MCContext &Ctx = MCOS->getContext();
+
+  for (auto &ProbeSec : MCProbeDivisions) {
+    const MCPseudoProbe *LastProbe = nullptr;
+    if (auto *S =
+            Ctx.getObjectFileInfo()->getPseudoProbeSection(ProbeSec.first)) {
+      // Switch to the .pseudoprobe section or a comdat group.
+      MCOS->SwitchSection(S);
+      // Emit probes grouped by GUID.
+      ProbeSec.second.emit(MCOS, LastProbe);
+    }
+  }
+}
+
+//
+// This emits the pseudo probe tables.
+//
+void MCPseudoProbeTable::emit(MCObjectStreamer *MCOS) {
+  MCContext &Ctx = MCOS->getContext();
+  auto &ProbeTable = Ctx.getMCPseudoProbeTable();
+
+  // Bail out early so we don't switch to the pseudo_probe section needlessly
+  // and in doing so create an unnecessary (if empty) section.
+  auto &ProbeSections = ProbeTable.getProbeSections();
+  if (ProbeSections.empty())
+    return;
+
+  LLVM_DEBUG(MCPseudoProbeTable::DdgPrintIndent = 0);
+
+  // Put out the probe.
+  ProbeSections.emit(MCOS);
+}