Update prebuilt Clang to r416183b from Android.

https://android.googlesource.com/platform/prebuilts/clang/host/
linux-x86/+/06a71ddac05c22edb2d10b590e1769b3f8619bef

clang 12.0.5 (based on r416183b) from build 7284624.

Change-Id: I277a316abcf47307562d8b748b84870f31a72866
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/linux-x64/clang/include/llvm/CodeGen/RDFLiveness.h b/linux-x64/clang/include/llvm/CodeGen/RDFLiveness.h
new file mode 100644
index 0000000..d39d358
--- /dev/null
+++ b/linux-x64/clang/include/llvm/CodeGen/RDFLiveness.h
@@ -0,0 +1,175 @@
+//===- RDFLiveness.h --------------------------------------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Recalculate the liveness information given a data flow graph.
+// This includes block live-ins and kill flags.
+
+#ifndef LLVM_LIB_TARGET_HEXAGON_RDFLIVENESS_H
+#define LLVM_LIB_TARGET_HEXAGON_RDFLIVENESS_H
+
+#include "RDFGraph.h"
+#include "RDFRegisters.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/MC/LaneBitmask.h"
+#include <map>
+#include <set>
+#include <unordered_map>
+#include <unordered_set>
+#include <utility>
+
+namespace llvm {
+
+class MachineBasicBlock;
+class MachineDominanceFrontier;
+class MachineDominatorTree;
+class MachineRegisterInfo;
+class TargetRegisterInfo;
+
+} // namespace llvm
+
+namespace llvm {
+namespace rdf {
+namespace detail {
+
+using NodeRef = std::pair<NodeId, LaneBitmask>;
+
+} // namespace detail
+} // namespace rdf
+} // namespace llvm
+
+namespace std {
+
+template <> struct hash<llvm::rdf::detail::NodeRef> {
+  std::size_t operator()(llvm::rdf::detail::NodeRef R) const {
+    return std::hash<llvm::rdf::NodeId>{}(R.first) ^
+           std::hash<llvm::LaneBitmask::Type>{}(R.second.getAsInteger());
+  }
+};
+
+} // namespace std
+
+namespace llvm {
+namespace rdf {
+
+  struct Liveness {
+  public:
+    // This is really a std::map, except that it provides a non-trivial
+    // default constructor to the element accessed via [].
+    struct LiveMapType {
+      LiveMapType(const PhysicalRegisterInfo &pri) : Empty(pri) {}
+
+      RegisterAggr &operator[] (MachineBasicBlock *B) {
+        return Map.emplace(B, Empty).first->second;
+      }
+
+    private:
+      RegisterAggr Empty;
+      std::map<MachineBasicBlock*,RegisterAggr> Map;
+    };
+
+    using NodeRef = detail::NodeRef;
+    using NodeRefSet = std::unordered_set<NodeRef>;
+    using RefMap = std::unordered_map<RegisterId, NodeRefSet>;
+
+    Liveness(MachineRegisterInfo &mri, const DataFlowGraph &g)
+        : DFG(g), TRI(g.getTRI()), PRI(g.getPRI()), MDT(g.getDT()),
+          MDF(g.getDF()), LiveMap(g.getPRI()), Empty(), NoRegs(g.getPRI()) {}
+
+    NodeList getAllReachingDefs(RegisterRef RefRR, NodeAddr<RefNode*> RefA,
+        bool TopShadows, bool FullChain, const RegisterAggr &DefRRs);
+
+    NodeList getAllReachingDefs(NodeAddr<RefNode*> RefA) {
+      return getAllReachingDefs(RefA.Addr->getRegRef(DFG), RefA, false,
+                                false, NoRegs);
+    }
+
+    NodeList getAllReachingDefs(RegisterRef RefRR, NodeAddr<RefNode*> RefA) {
+      return getAllReachingDefs(RefRR, RefA, false, false, NoRegs);
+    }
+
+    NodeSet getAllReachedUses(RegisterRef RefRR, NodeAddr<DefNode*> DefA,
+        const RegisterAggr &DefRRs);
+
+    NodeSet getAllReachedUses(RegisterRef RefRR, NodeAddr<DefNode*> DefA) {
+      return getAllReachedUses(RefRR, DefA, NoRegs);
+    }
+
+    std::pair<NodeSet,bool> getAllReachingDefsRec(RegisterRef RefRR,
+        NodeAddr<RefNode*> RefA, NodeSet &Visited, const NodeSet &Defs);
+
+    NodeAddr<RefNode*> getNearestAliasedRef(RegisterRef RefRR,
+        NodeAddr<InstrNode*> IA);
+
+    LiveMapType &getLiveMap() { return LiveMap; }
+    const LiveMapType &getLiveMap() const { return LiveMap; }
+
+    const RefMap &getRealUses(NodeId P) const {
+      auto F = RealUseMap.find(P);
+      return F == RealUseMap.end() ? Empty : F->second;
+    }
+
+    void computePhiInfo();
+    void computeLiveIns();
+    void resetLiveIns();
+    void resetKills();
+    void resetKills(MachineBasicBlock *B);
+
+    void trace(bool T) { Trace = T; }
+
+  private:
+    const DataFlowGraph &DFG;
+    const TargetRegisterInfo &TRI;
+    const PhysicalRegisterInfo &PRI;
+    const MachineDominatorTree &MDT;
+    const MachineDominanceFrontier &MDF;
+    LiveMapType LiveMap;
+    const RefMap Empty;
+    const RegisterAggr NoRegs;
+    bool Trace = false;
+
+    // Cache of mapping from node ids (for RefNodes) to the containing
+    // basic blocks. Not computing it each time for each node reduces
+    // the liveness calculation time by a large fraction.
+    DenseMap<NodeId, MachineBasicBlock *> NBMap;
+
+    // Phi information:
+    //
+    // RealUseMap
+    // map: NodeId -> (map: RegisterId -> NodeRefSet)
+    //      phi id -> (map: register -> set of reached non-phi uses)
+    DenseMap<NodeId, RefMap> RealUseMap;
+
+    // Inverse iterated dominance frontier.
+    std::map<MachineBasicBlock*,std::set<MachineBasicBlock*>> IIDF;
+
+    // Live on entry.
+    std::map<MachineBasicBlock*,RefMap> PhiLON;
+
+    // Phi uses are considered to be located at the end of the block that
+    // they are associated with. The reaching def of a phi use dominates the
+    // block that the use corresponds to, but not the block that contains
+    // the phi itself. To include these uses in the liveness propagation (up
+    // the dominator tree), create a map: block -> set of uses live on exit.
+    std::map<MachineBasicBlock*,RefMap> PhiLOX;
+
+    MachineBasicBlock *getBlockWithRef(NodeId RN) const;
+    void traverse(MachineBasicBlock *B, RefMap &LiveIn);
+    void emptify(RefMap &M);
+
+    std::pair<NodeSet,bool> getAllReachingDefsRecImpl(RegisterRef RefRR,
+        NodeAddr<RefNode*> RefA, NodeSet &Visited, const NodeSet &Defs,
+        unsigned Nest, unsigned MaxNest);
+  };
+
+  raw_ostream &operator<<(raw_ostream &OS, const Print<Liveness::RefMap> &P);
+
+} // end namespace rdf
+
+} // end namespace llvm
+
+#endif // LLVM_LIB_TARGET_HEXAGON_RDFLIVENESS_H