Import prebuilt clang toolchain for linux.
diff --git a/linux-x64/clang/include/llvm/IR/DebugInfo.h b/linux-x64/clang/include/llvm/IR/DebugInfo.h
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+++ b/linux-x64/clang/include/llvm/IR/DebugInfo.h
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+//===- DebugInfo.h - Debug Information Helpers ------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines a bunch of datatypes that are useful for creating and
+// walking debug info in LLVM IR form. They essentially provide wrappers around
+// the information in the global variables that's needed when constructing the
+// DWARF information.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_IR_DEBUGINFO_H
+#define LLVM_IR_DEBUGINFO_H
+
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/iterator_range.h"
+#include "llvm/IR/DebugInfoMetadata.h"
+
+namespace llvm {
+
+class DbgDeclareInst;
+class DbgValueInst;
+class Module;
+
+/// \brief Find subprogram that is enclosing this scope.
+DISubprogram *getDISubprogram(const MDNode *Scope);
+
+/// \brief Strip debug info in the module if it exists.
+///
+/// To do this, we remove all calls to the debugger intrinsics and any named
+/// metadata for debugging. We also remove debug locations for instructions.
+/// Return true if module is modified.
+bool StripDebugInfo(Module &M);
+bool stripDebugInfo(Function &F);
+
+/// Downgrade the debug info in a module to contain only line table information.
+///
+/// In order to convert debug info to what -gline-tables-only would have
+/// created, this does the following:
+///   1) Delete all debug intrinsics.
+///   2) Delete all non-CU named metadata debug info nodes.
+///   3) Create new DebugLocs for each instruction.
+///   4) Create a new CU debug info, and similarly for every metadata node
+///      that's reachable from the CU debug info.
+///   All debug type metadata nodes are unreachable and garbage collected.
+bool stripNonLineTableDebugInfo(Module &M);
+
+/// \brief Return Debug Info Metadata Version by checking module flags.
+unsigned getDebugMetadataVersionFromModule(const Module &M);
+
+/// \brief Utility to find all debug info in a module.
+///
+/// DebugInfoFinder tries to list all debug info MDNodes used in a module. To
+/// list debug info MDNodes used by an instruction, DebugInfoFinder uses
+/// processDeclare, processValue and processLocation to handle DbgDeclareInst,
+/// DbgValueInst and DbgLoc attached to instructions. processModule will go
+/// through all DICompileUnits in llvm.dbg.cu and list debug info MDNodes
+/// used by the CUs.
+class DebugInfoFinder {
+public:
+  /// \brief Process entire module and collect debug info anchors.
+  void processModule(const Module &M);
+
+  /// \brief Process DbgDeclareInst.
+  void processDeclare(const Module &M, const DbgDeclareInst *DDI);
+  /// \brief Process DbgValueInst.
+  void processValue(const Module &M, const DbgValueInst *DVI);
+  /// \brief Process debug info location.
+  void processLocation(const Module &M, const DILocation *Loc);
+
+  /// \brief Clear all lists.
+  void reset();
+
+private:
+  void InitializeTypeMap(const Module &M);
+
+  void processType(DIType *DT);
+  void processSubprogram(DISubprogram *SP);
+  void processScope(DIScope *Scope);
+  bool addCompileUnit(DICompileUnit *CU);
+  bool addGlobalVariable(DIGlobalVariableExpression *DIG);
+  bool addSubprogram(DISubprogram *SP);
+  bool addType(DIType *DT);
+  bool addScope(DIScope *Scope);
+
+public:
+  using compile_unit_iterator =
+      SmallVectorImpl<DICompileUnit *>::const_iterator;
+  using subprogram_iterator = SmallVectorImpl<DISubprogram *>::const_iterator;
+  using global_variable_expression_iterator =
+      SmallVectorImpl<DIGlobalVariableExpression *>::const_iterator;
+  using type_iterator = SmallVectorImpl<DIType *>::const_iterator;
+  using scope_iterator = SmallVectorImpl<DIScope *>::const_iterator;
+
+  iterator_range<compile_unit_iterator> compile_units() const {
+    return make_range(CUs.begin(), CUs.end());
+  }
+
+  iterator_range<subprogram_iterator> subprograms() const {
+    return make_range(SPs.begin(), SPs.end());
+  }
+
+  iterator_range<global_variable_expression_iterator> global_variables() const {
+    return make_range(GVs.begin(), GVs.end());
+  }
+
+  iterator_range<type_iterator> types() const {
+    return make_range(TYs.begin(), TYs.end());
+  }
+
+  iterator_range<scope_iterator> scopes() const {
+    return make_range(Scopes.begin(), Scopes.end());
+  }
+
+  unsigned compile_unit_count() const { return CUs.size(); }
+  unsigned global_variable_count() const { return GVs.size(); }
+  unsigned subprogram_count() const { return SPs.size(); }
+  unsigned type_count() const { return TYs.size(); }
+  unsigned scope_count() const { return Scopes.size(); }
+
+private:
+  SmallVector<DICompileUnit *, 8> CUs;
+  SmallVector<DISubprogram *, 8> SPs;
+  SmallVector<DIGlobalVariableExpression *, 8> GVs;
+  SmallVector<DIType *, 8> TYs;
+  SmallVector<DIScope *, 8> Scopes;
+  SmallPtrSet<const MDNode *, 32> NodesSeen;
+};
+
+} // end namespace llvm
+
+#endif // LLVM_IR_DEBUGINFO_H