Temporarily revert r72191. It was causing an assert during llvm-gcc
bootstrapping.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72200 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 438ba03..45462da 100644
--- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -1311,7 +1311,7 @@
 void AsmPrinter::processDebugLoc(DebugLoc DL) {
   if (TAI->doesSupportDebugInformation() && DW->ShouldEmitDwarfDebug()) {
     if (!DL.isUnknown()) {
-      static DebugLocTuple PrevDLT(0, DebugScope::getInvalid(), ~0U, ~0U);
+      static DebugLocTuple PrevDLT(0, ~0U, ~0U);
       DebugLocTuple CurDLT = MF->getDebugLocTuple(DL);
 
       if (CurDLT.CompileUnit != 0 && PrevDLT != CurDLT)
diff --git a/lib/CodeGen/DebugLoc.cpp b/lib/CodeGen/DebugLoc.cpp
deleted file mode 100644
index bc1a5b1..0000000
--- a/lib/CodeGen/DebugLoc.cpp
+++ /dev/null
@@ -1,38 +0,0 @@
-//===-- DebugLoc.cpp ------------------------------------------------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// Implementation for DebugScopeTracker.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/CodeGen/DebugLoc.h"
-#include "llvm/CodeGen/MachineFunction.h"
-using namespace llvm;
-
-/// EnterDebugScope - Start a new debug scope. ScopeGV can be a DISubprogram
-/// or a DIBlock.
-void DebugScopeTracker::EnterDebugScope(GlobalVariable *ScopeGV,
-                                        MachineFunction &MF) {
-  assert(ScopeGV && "GlobalVariable for scope is null!");
-  CurScope = MF.CreateDebugScope(ScopeGV, CurScope);
-}
-
-/// ExitDebugScope - "Pop" a DISubprogram or a DIBlock.
-void DebugScopeTracker::ExitDebugScope(GlobalVariable *ScopeGV,
-                                       MachineFunction &MF) {
-  assert(ScopeGV && "GlobalVariable for scope is null!");
-  assert(!CurScope.isInvalid() && "Mismatched region.end ?");
-  // We may have skipped a region.end because it was in an unreachable block.
-  // Go up the scope chain until we reach the scope that ScopeGV points to.
-  DebugScopeInfo DSI;
-  do {
-    DSI =  MF.getDebugScopeInfo(CurScope);
-    CurScope = DSI.Parent;
-  } while (!DSI.Parent.isInvalid() && DSI.GV != ScopeGV);
-}
diff --git a/lib/CodeGen/MachineFunction.cpp b/lib/CodeGen/MachineFunction.cpp
index d1d782c..cacfed1 100644
--- a/lib/CodeGen/MachineFunction.cpp
+++ b/lib/CodeGen/MachineFunction.cpp
@@ -403,9 +403,8 @@
 /// source file, line, and column. If none currently exists, create a new
 /// DebugLocTuple, and insert it into the DebugIdMap.
 unsigned MachineFunction::getOrCreateDebugLocID(GlobalVariable *CompileUnit,
-                                                DebugScope Scope,
                                                 unsigned Line, unsigned Col) {
-  DebugLocTuple Tuple(CompileUnit, Scope, Line, Col);
+  DebugLocTuple Tuple(CompileUnit, Line, Col);
   DenseMap<DebugLocTuple, unsigned>::iterator II
     = DebugLocInfo.DebugIdMap.find(Tuple);
   if (II != DebugLocInfo.DebugIdMap.end())
@@ -425,21 +424,6 @@
   return DebugLocInfo.DebugLocations[Idx];
 }
 
-/// CreateDebugScope - Create a new debug scope.
-DebugScope MachineFunction::CreateDebugScope(GlobalVariable *ScopeGV,
-                                             DebugScope Parent) {
-  DbgScopeInfos.push_back(DebugScopeInfo(ScopeGV, Parent));
-  return DebugScope::get(DbgScopeInfos.size() - 1);
-}
-
-/// getDebugScopeInfo - Get the DebugScopeInfo for a given DebugScope object.
-const DebugScopeInfo &MachineFunction::getDebugScopeInfo(DebugScope DS) const {
-  unsigned Idx = DS.getIndex();
-  assert(Idx < DbgScopeInfos.size() && "Invalid index into debug scopes!");
-  return DbgScopeInfos[Idx];
-}
-
-
 //===----------------------------------------------------------------------===//
 //  MachineFrameInfo implementation
 //===----------------------------------------------------------------------===//
diff --git a/lib/CodeGen/SelectionDAG/FastISel.cpp b/lib/CodeGen/SelectionDAG/FastISel.cpp
index 1c05b0a..367cf4c 100644
--- a/lib/CodeGen/SelectionDAG/FastISel.cpp
+++ b/lib/CodeGen/SelectionDAG/FastISel.cpp
@@ -331,22 +331,17 @@
       DICompileUnit CU(cast<GlobalVariable>(SPI->getContext()));
       unsigned Line = SPI->getLine();
       unsigned Col = SPI->getColumn();
-      unsigned Idx = MF.getOrCreateDebugLocID(CU.getGV(),
-                                              DbgScopeTrack.getCurScope(),
-                                              Line, Col);
+      unsigned Idx = MF.getOrCreateDebugLocID(CU.getGV(), Line, Col);
       setCurDebugLoc(DebugLoc::get(Idx));
     }
     return true;
   }
   case Intrinsic::dbg_region_start: {
     DbgRegionStartInst *RSI = cast<DbgRegionStartInst>(I);
-    if (!DIDescriptor::ValidDebugInfo(RSI->getContext(), CodeGenOpt::None))
-      return true;
-
-    GlobalVariable *Rgn = cast<GlobalVariable>(RSI->getContext());
-    DbgScopeTrack.EnterDebugScope(Rgn, MF);
-    if (DW && DW->ShouldEmitDwarfDebug()) {
-      unsigned ID = DW->RecordRegionStart(Rgn);
+    if (DIDescriptor::ValidDebugInfo(RSI->getContext(), CodeGenOpt::None) &&
+        DW && DW->ShouldEmitDwarfDebug()) {
+      unsigned ID = 
+        DW->RecordRegionStart(cast<GlobalVariable>(RSI->getContext()));
       const TargetInstrDesc &II = TII.get(TargetInstrInfo::DBG_LABEL);
       BuildMI(MBB, DL, II).addImm(ID);
     }
@@ -354,14 +349,10 @@
   }
   case Intrinsic::dbg_region_end: {
     DbgRegionEndInst *REI = cast<DbgRegionEndInst>(I);
-    if (!DIDescriptor::ValidDebugInfo(REI->getContext(), CodeGenOpt::None))
-      return true;
-
-    GlobalVariable *Rgn = cast<GlobalVariable>(REI->getContext());
-    DbgScopeTrack.ExitDebugScope(Rgn, MF);
-    if (DW && DW->ShouldEmitDwarfDebug()) {
+    if (DIDescriptor::ValidDebugInfo(REI->getContext(), CodeGenOpt::None) &&
+        DW && DW->ShouldEmitDwarfDebug()) {
      unsigned ID = 0;
-     DISubprogram Subprogram(Rgn);
+     DISubprogram Subprogram(cast<GlobalVariable>(REI->getContext()));
      if (!Subprogram.isNull() && !Subprogram.describes(MF.getFunction())) {
         // This is end of an inlined function.
         const TargetInstrDesc &II = TII.get(TargetInstrInfo::DBG_LABEL);
@@ -391,7 +382,6 @@
     DebugLoc PrevLoc = DL;
     DISubprogram Subprogram(cast<GlobalVariable>(SP));
     DICompileUnit CompileUnit = Subprogram.getCompileUnit();
-    DbgScopeTrack.EnterDebugScope(Subprogram.getGV(), MF);
 
     if (!Subprogram.describes(MF.getFunction())) {
       // This is a beginning of an inlined function.
@@ -403,10 +393,8 @@
         return true;
       // Record the source line.
       unsigned Line = Subprogram.getLineNumber();
-      setCurDebugLoc(
-        DebugLoc::get(MF.getOrCreateDebugLocID(CompileUnit.getGV(),
-                                               DbgScopeTrack.getCurScope(),
-                                               Line, 0)));
+      setCurDebugLoc(DebugLoc::get(MF.getOrCreateDebugLocID(
+                                              CompileUnit.getGV(), Line, 0)));
 
       if (DW && DW->ShouldEmitDwarfDebug()) {
         DebugLocTuple PrevLocTpl = MF.getDebugLocTuple(PrevLoc);
@@ -420,10 +408,8 @@
     } else {
       // Record the source line.
       unsigned Line = Subprogram.getLineNumber();
-      MF.setDefaultDebugLoc(
-        DebugLoc::get(MF.getOrCreateDebugLocID(CompileUnit.getGV(),
-                                               DbgScopeTrack.getCurScope(),
-                                               Line, 0)));
+      MF.setDefaultDebugLoc(DebugLoc::get(MF.getOrCreateDebugLocID(
+                                              CompileUnit.getGV(), Line, 0)));
       if (DW && DW->ShouldEmitDwarfDebug()) {
         // llvm.dbg.func_start also defines beginning of function scope.
         DW->RecordRegionStart(cast<GlobalVariable>(FSI->getSubprogram()));
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp
index f0b1ec8..430dcfd 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuild.cpp
@@ -312,17 +312,6 @@
             !StaticAllocaMap.count(cast<AllocaInst>(I)))
           InitializeRegForValue(I);
 
-  // FIXME: PHI instructions currently get an invalid scope. This is because
-  // tracking of debug scopes is done through a simple mechanism where
-  // "entering" a scope implies that the scope is entered for the first time.
-  // If we keep track of debug scopes for the following loop, the PHI
-  // instructions would get scopes that will not be used again later by the
-  // instruction selectors.
-  // Either provide a mechanism to re-enter a previously created scope or wait
-  // for when the DebugLoc is retrieved from Instruction, in which case the
-  // current debug scope tracking mechanism will be obsolete.
-  DebugScope DbgScope;
-
   // Create an initial MachineBasicBlock for each LLVM BasicBlock in F.  This
   // also creates the initial PHI MachineInstrs, though none of the input
   // operands are populated.
@@ -348,7 +337,6 @@
                                              CodeGenOpt::Default)) {
               DICompileUnit CU(cast<GlobalVariable>(SPI->getContext()));
               unsigned idx = MF->getOrCreateDebugLocID(CU.getGV(),
-                                                       DbgScope,
                                                        SPI->getLine(),
                                                        SPI->getColumn());
               DL = DebugLoc::get(idx);
@@ -364,7 +352,7 @@
               DISubprogram Subprogram(cast<GlobalVariable>(SP));
               DICompileUnit CU(Subprogram.getCompileUnit());
               unsigned Line = Subprogram.getLineNumber();
-              DL = DebugLoc::get(MF->getOrCreateDebugLocID(CU.getGV(), DbgScope,
+              DL = DebugLoc::get(MF->getOrCreateDebugLocID(CU.getGV(),
                                                            Line, 0));
             }
 
@@ -3921,9 +3909,7 @@
       MachineFunction &MF = DAG.getMachineFunction();
       DICompileUnit CU(cast<GlobalVariable>(SPI.getContext()));
       DebugLoc Loc = DebugLoc::get(MF.getOrCreateDebugLocID(CU.getGV(),
-                                                 DbgScopeTrack.getCurScope(),
-                                                           SPI.getLine(),
-                                                           SPI.getColumn()));
+                                              SPI.getLine(), SPI.getColumn()));
       setCurDebugLoc(Loc);
       
       if (OptLevel == CodeGenOpt::None)
@@ -3937,14 +3923,11 @@
   case Intrinsic::dbg_region_start: {
     DwarfWriter *DW = DAG.getDwarfWriter();
     DbgRegionStartInst &RSI = cast<DbgRegionStartInst>(I);
-    if (!DIDescriptor::ValidDebugInfo(RSI.getContext(), OptLevel))
-      return 0;
 
-    MachineFunction &MF = DAG.getMachineFunction();
-    GlobalVariable *Rgn = cast<GlobalVariable>(RSI.getContext());
-    DbgScopeTrack.EnterDebugScope(Rgn, MF);
-    if (DW && DW->ShouldEmitDwarfDebug()) {
-      unsigned LabelID = DW->RecordRegionStart(Rgn);
+    if (DIDescriptor::ValidDebugInfo(RSI.getContext(), OptLevel) &&
+        DW && DW->ShouldEmitDwarfDebug()) {
+      unsigned LabelID =
+        DW->RecordRegionStart(cast<GlobalVariable>(RSI.getContext()));
       DAG.setRoot(DAG.getLabel(ISD::DBG_LABEL, getCurDebugLoc(),
                                getRoot(), LabelID));
     }
@@ -3954,14 +3937,11 @@
   case Intrinsic::dbg_region_end: {
     DwarfWriter *DW = DAG.getDwarfWriter();
     DbgRegionEndInst &REI = cast<DbgRegionEndInst>(I);
-    if (!DIDescriptor::ValidDebugInfo(REI.getContext(), OptLevel))
-      return 0;
 
-    MachineFunction &MF = DAG.getMachineFunction();
-    GlobalVariable *Rgn = cast<GlobalVariable>(REI.getContext());
-    DbgScopeTrack.ExitDebugScope(Rgn, MF);
-    if (DW && DW->ShouldEmitDwarfDebug()) {
-      DISubprogram Subprogram(Rgn);
+    if (DIDescriptor::ValidDebugInfo(REI.getContext(), OptLevel) &&
+        DW && DW->ShouldEmitDwarfDebug()) {
+      MachineFunction &MF = DAG.getMachineFunction();
+      DISubprogram Subprogram(cast<GlobalVariable>(REI.getContext()));
 
       if (Subprogram.isNull() || Subprogram.describes(MF.getFunction())) {
         unsigned LabelID =
@@ -3994,7 +3974,6 @@
       return 0;
 
     MachineFunction &MF = DAG.getMachineFunction();
-    DbgScopeTrack.EnterDebugScope(cast<GlobalVariable>(SP), MF);
     if (OptLevel == CodeGenOpt::None) {
       // llvm.dbg.func.start implicitly defines a dbg_stoppoint which is what
       // (most?) gdb expects.
@@ -4014,9 +3993,7 @@
         // Record the source line.
         unsigned Line = Subprogram.getLineNumber();
         setCurDebugLoc(DebugLoc::get(
-                     MF.getOrCreateDebugLocID(CompileUnit.getGV(),
-                                              DbgScopeTrack.getCurScope(),
-                                              Line, 0)));
+                     MF.getOrCreateDebugLocID(CompileUnit.getGV(), Line, 0)));
 
         if (DW && DW->ShouldEmitDwarfDebug()) {
           DebugLocTuple PrevLocTpl = MF.getDebugLocTuple(PrevLoc);
@@ -4031,9 +4008,7 @@
         // Record the source line.
         unsigned Line = Subprogram.getLineNumber();
         MF.setDefaultDebugLoc(DebugLoc::get(
-                     MF.getOrCreateDebugLocID(CompileUnit.getGV(),
-                                              DbgScopeTrack.getCurScope(),
-                                              Line, 0)));
+                     MF.getOrCreateDebugLocID(CompileUnit.getGV(), Line, 0)));
         if (DW && DW->ShouldEmitDwarfDebug()) {
           // llvm.dbg.func_start also defines beginning of function scope.
           DW->RecordRegionStart(cast<GlobalVariable>(FSI.getSubprogram()));
@@ -4060,9 +4035,7 @@
       // create a label if this is a beginning of inlined function.
       unsigned Line = Subprogram.getLineNumber();
       setCurDebugLoc(DebugLoc::get(
-                     MF.getOrCreateDebugLocID(CompileUnit.getGV(),
-                                              DbgScopeTrack.getCurScope(),
-                                              Line, 0)));
+                     MF.getOrCreateDebugLocID(CompileUnit.getGV(), Line, 0)));
       // FIXME -  Start new region because llvm.dbg.func_start also defines
       // beginning of function scope.
     }
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGBuild.h b/lib/CodeGen/SelectionDAG/SelectionDAGBuild.h
index 0c9b317..578aa591 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGBuild.h
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGBuild.h
@@ -169,8 +169,6 @@
   /// CurDebugLoc - current file + line number.  Changes as we build the DAG.
   DebugLoc CurDebugLoc;
 
-  DebugScopeTracker DbgScopeTrack;
-
   DenseMap<const Value*, SDValue> NodeMap;
 
   /// PendingLoads - Loads are not emitted to the program immediately.  We bunch