1 files changed, 55 insertions, 6 deletions

diff --git a/llvm/lib/DebugInfo/DWARFDebugLine.h b/llvm/lib/DebugInfo/DWARFDebugLine.h
index a8c0669b738..6382b45a93a 100644
--- a/llvm/lib/DebugInfo/DWARFDebugLine.h
+++ b/llvm/lib/DebugInfo/DWARFDebugLine.h
@@ -88,6 +88,10 @@ public:
     void reset(bool default_is_stmt);
     void dump(raw_ostream &OS) const;
 
+    static bool orderByAddress(const Row& LHS, const Row& RHS) {
+      return LHS.Address < RHS.Address;
+    }
+
     // The program-counter value corresponding to a machine instruction
     // generated by the compiler.
     uint64_t Address;
@@ -125,21 +129,63 @@ public:
             EpilogueBegin:1;
   };
 
+  // Represents a series of contiguous machine instructions. Line table for each
+  // compilation unit may consist of multiple sequences, which are not
+  // guaranteed to be in the order of ascending instruction address.
+  struct Sequence {
+    // Sequence describes instructions at address range [LowPC, HighPC)
+    // and is described by line table rows [FirstRowIndex, LastRowIndex).
+    uint64_t LowPC;
+    uint64_t HighPC;
+    unsigned FirstRowIndex;
+    unsigned LastRowIndex;
+    bool Empty;
+
+    Sequence() { reset(); }
+    void reset() {
+      LowPC = 0;
+      HighPC = 0;
+      FirstRowIndex = 0;
+      LastRowIndex = 0;
+      Empty = true;
+    }
+    static bool orderByLowPC(const Sequence& LHS, const Sequence& RHS) {
+      return LHS.LowPC < RHS.LowPC;
+    }
+    bool isValid() const {
+      return !Empty && (LowPC < HighPC) && (FirstRowIndex < LastRowIndex);
+    }
+    bool containsPC(uint64_t pc) const {
+      return (LowPC <= pc && pc < HighPC);
+    }
+  };
+
   struct LineTable {
     void appendRow(const DWARFDebugLine::Row &state) { Rows.push_back(state); }
+    void appendSequence(const DWARFDebugLine::Sequence &sequence) {
+      Sequences.push_back(sequence);
+    }
     void clear() {
       Prologue.clear();
       Rows.clear();
+      Sequences.clear();
     }
 
-    uint32_t lookupAddress(uint64_t address, uint64_t cu_high_pc) const;
+    // Returns the index of the row with file/line info for a given address,
+    // or -1 if there is no such row.
+    uint32_t lookupAddress(uint64_t address) const;
     void dump(raw_ostream &OS) const;
 
     struct Prologue Prologue;
-    std::vector<Row> Rows;
+    typedef std::vector<Row> RowVector;
+    typedef RowVector::const_iterator RowIter;
+    typedef std::vector<Sequence> SequenceVector;
+    typedef SequenceVector::const_iterator SequenceIter;
+    RowVector Rows;
+    SequenceVector Sequences;
   };
 
-  struct State : public Row, public LineTable {
+  struct State : public Row, public Sequence, public LineTable {
     // Special row codes.
     enum {
       StartParsingLineTable = 0,
@@ -150,8 +196,11 @@ public:
     virtual ~State();
 
     virtual void appendRowToMatrix(uint32_t offset);
-    virtual void finalize(uint32_t offset) { row = DoneParsingLineTable; }
-    virtual void reset() { Row::reset(Prologue.DefaultIsStmt); }
+    virtual void finalize();
+    virtual void reset() {
+      Row::reset(Prologue.DefaultIsStmt);
+      Sequence::reset();
+    }
 
     // The row number that starts at zero for the prologue, and increases for
     // each row added to the matrix.
@@ -161,7 +210,7 @@ public:
   struct DumpingState : public State {
     DumpingState(raw_ostream &OS) : OS(OS) {}
     virtual ~DumpingState();
-    virtual void finalize(uint32_t offset);
+    virtual void finalize();
   private:
     raw_ostream &OS;
   };