Refactor code to push DILocation prcessing into DwarfDebug.cpp from AsmPrinter.cpp.

This is same as r99772 (which was reverted) with just one meaningful difference where two source lines exchanged their positions.

llvm-svn: 99816

1 files changed, 42 insertions, 3 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index e2421eb0702..1d00e0abcc8 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -296,7 +296,7 @@ DwarfDebug::DwarfDebug(raw_ostream &OS, AsmPrinter *A, const MCAsmInfo *T)
   : DwarfPrinter(OS, A, T), ModuleCU(0),
     AbbreviationsSet(InitAbbreviationsSetSize), Abbreviations(),
     DIEValues(), SectionSourceLines(), didInitial(false), shouldEmit(false),
-    CurrentFnDbgScope(0), DebugTimer(0) {
+    CurrentFnDbgScope(0), PrevDILoc(0), DebugTimer(0) {
   NextStringPoolNumber = 0;
   if (TimePassesIsEnabled)
     DebugTimer = new Timer("Dwarf Debug Writer");
@@ -2036,19 +2036,58 @@ void DwarfDebug::collectVariableInfo() {
   }
 }
 
-/// beginScope - Process beginning of a scope starting at Label.
-void DwarfDebug::beginScope(const MachineInstr *MI, MCSymbol *Label) {
+/// beginScope - Process beginning of a scope.
+void DwarfDebug::beginScope(const MachineInstr *MI) {
+  // Ignore DBG_VALUE instructions.
+  if (MI->getOpcode() == TargetOpcode::DBG_VALUE)
+    return;
+
+  // Check location.
+  DebugLoc DL = MI->getDebugLoc();
+  if (DL.isUnknown())
+    return;
+  DILocation DILoc = MF->getDILocation(DL);
+  if (!DILoc.getScope().Verify())
+    return;
+
+  // Check and update last known location info.
+  if(DILoc.getNode() == PrevDILoc)
+    return;
+  PrevDILoc = DILoc.getNode();
+
+  // Emit a label to indicate location change. This is used for line 
+  // table even if this instruction does start a new scope.
+  MCSymbol *Label = recordSourceLine(DILoc.getLineNumber(),
+                                     DILoc.getColumnNumber(),
+                                     DILoc.getScope().getNode());
+
+  // update DbgScope if this instruction starts a new scope.
   InsnToDbgScopeMapTy::iterator I = DbgScopeBeginMap.find(MI);
   if (I == DbgScopeBeginMap.end())
     return;
+
   ScopeVector &SD = I->second;
   for (ScopeVector::iterator SDI = SD.begin(), SDE = SD.end();
        SDI != SDE; ++SDI)
     (*SDI)->setStartLabel(Label);
+
 }
 
 /// endScope - Process end of a scope.
 void DwarfDebug::endScope(const MachineInstr *MI) {
+  // Ignore DBG_VALUE instruction.
+  if (MI->getOpcode() == TargetOpcode::DBG_VALUE)
+    return;
+
+  // Check location.
+  DebugLoc DL = MI->getDebugLoc();
+  if (DL.isUnknown())
+    return;
+  DILocation DILoc = MF->getDILocation(DL);
+  if (!DILoc.getScope().Verify())
+    return;
+  
+  // Emit a label and update DbgScope if this instruction ends a scope.
   InsnToDbgScopeMapTy::iterator I = DbgScopeEndMap.find(MI);
   if (I == DbgScopeEndMap.end())
     return;