1. Add a pass to fold debug label instructions so a debug info client can detect

empty ranges.

2. Reorg how MachineDebugInfo maintains changes to debug labels.

3. Have dwarf writer use debug label info to simplify scopes and source line
coorespondence.

4. Revert the merging of compile units until I can get the bugs ironed out.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31507 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 20 insertions, 17 deletions

diff --git a/lib/CodeGen/DwarfWriter.cpp b/lib/CodeGen/DwarfWriter.cpp
index 81c8963e16..c8a1333d6c 100644
--- a/lib/CodeGen/DwarfWriter.cpp
+++ b/lib/CodeGen/DwarfWriter.cpp
@@ -1695,15 +1695,18 @@ private:
     return Unit;
   }
 
+  /// GetBaseCompileUnit - Get the main compile unit.
+  ///
+  CompileUnit *GetBaseCompileUnit() const {
+    CompileUnit *Unit = CompileUnits[0];
+    assert(Unit && "Missing compile unit.");
+    return Unit;
+  }
+
   /// FindCompileUnit - Get the compile unit for the given descriptor.
   ///
   CompileUnit *FindCompileUnit(CompileUnitDesc *UnitDesc) {
-#if 1
-    // FIXME - Using only one compile unit.  Needs to me fixed at the FE.
-    CompileUnit *Unit = CompileUnits[0];
-#else
     CompileUnit *Unit = DescToUnitMap[UnitDesc];
-#endif
     assert(Unit && "Missing compile unit.");
     return Unit;
   }
@@ -1859,13 +1862,12 @@ private:
       // FIXME - Ignore inlined functions for the time being.
       if (!Scope->getParent()) continue;
       
-      unsigned StartID = Scope->getStartLabelID();
-      unsigned EndID = Scope->getEndLabelID();
+      unsigned StartID = DebugInfo->MappedLabel(Scope->getStartLabelID());
+      unsigned EndID = DebugInfo->MappedLabel(Scope->getEndLabelID());
       
-      // Widen scope if label is discarded.
-      // FIXME - really need to find a GOOD label if a block is dead.
-      if (StartID && !DebugInfo->isLabelValid(StartID)) StartID = 0;
-      if (EndID && !DebugInfo->isLabelValid(EndID)) EndID = 0;
+      // Ignore empty scopes.
+      if (StartID == EndID && StartID != 0) continue;
+      if (Scope->getScopes().empty() && Scope->getVariables().empty()) continue;
       
       DIE *ScopeDie = new DIE(DW_TAG_lexical_block);
       
@@ -2084,10 +2086,10 @@ private:
                                    std::vector<MachineMove *> &Moves) {
     for (unsigned i = 0, N = Moves.size(); i < N; ++i) {
       MachineMove *Move = Moves[i];
-      unsigned LabelID = Move->getLabelID();
+      unsigned LabelID = DebugInfo->MappedLabel(Move->getLabelID());
       
       // Throw out move if the label is invalid.
-      if (LabelID && !DebugInfo->isLabelValid(LabelID)) continue;
+      if (!LabelID) continue;
       
       const MachineLocation &Dst = Move->getDestination();
       const MachineLocation &Src = Move->getSource();
@@ -2307,9 +2309,8 @@ private:
       // Construct rows of the address, source, line, column matrix.
       for (unsigned i = 0, N = LineInfos.size(); i < N; ++i) {
         const SourceLineInfo &LineInfo = LineInfos[i];
-        unsigned LabelID = LineInfo.getLabelID();
-        
-        // Source line labels are validated at the MachineDebugInfo level.
+        unsigned LabelID = DebugInfo->MappedLabel(LineInfo.getLabelID());
+        if (!LabelID) continue;
         
         if (DwarfVerbose) {
           unsigned SourceID = LineInfo.getSourceID();
@@ -2420,6 +2421,7 @@ private:
   void EmitFunctionDebugFrame() {
     if (!TAI->getDwarfRequiresFrameSection())
       return;
+       
     // Start the dwarf frame section.
     Asm->SwitchToDataSection(TAI->getDwarfFrameSection());
     
@@ -2588,7 +2590,8 @@ private:
     const UniqueVector<CompileUnitDesc *> CUW = DebugInfo->getCompileUnits();
     
     for (unsigned i = 1, N = CUW.size(); i <= N; ++i) {
-      CompileUnit *Unit = NewCompileUnit(CUW[i], i);
+      unsigned ID = DebugInfo->RecordSource(CUW[i]);
+      CompileUnit *Unit = NewCompileUnit(CUW[i], ID);
       CompileUnits.push_back(Unit);
     }
   }