There are two ways to map a variable to its lexical scope. Lexical scope information is embedded in MDNode describing the variable. It is also available as a part of DebugLoc attached with DBG_VALUE instruction. DebugLoc attached with an instruction is less reliable in optimized code so use information embedded in the MDNode.

llvm-svn: 135629

3 files changed, 18 insertions, 2 deletions

diff --git a/llvm/include/llvm/Analysis/DebugInfo.h b/llvm/include/llvm/Analysis/DebugInfo.h
index 152d11ef93a..929dd1d13a7 100644
--- a/llvm/include/llvm/Analysis/DebugInfo.h
+++ b/llvm/include/llvm/Analysis/DebugInfo.h
@@ -614,6 +614,8 @@ namespace llvm {
       return (getUnsignedField(6) & FlagArtificial) != 0;
     }
 
+    /// getInlinedAt - If this variable is inlined then return inline location.
+    MDNode *getInlinedAt();
 
     /// Verify - Verify that a variable descriptor is well formed.
     bool Verify() const;
diff --git a/llvm/lib/Analysis/DebugInfo.cpp b/llvm/lib/Analysis/DebugInfo.cpp
index 4dcf04ef216..dd85a4fcc80 100644
--- a/llvm/lib/Analysis/DebugInfo.cpp
+++ b/llvm/lib/Analysis/DebugInfo.cpp
@@ -116,6 +116,12 @@ unsigned DIVariable::getNumAddrElements() const {
   return DbgNode->getNumOperands()-8;
 }
 
+/// getInlinedAt - If this variable is inlined then return inline location.
+MDNode *DIVariable::getInlinedAt() {
+  if (getVersion() <= llvm::LLVMDebugVersion9)
+    return NULL;
+  return dyn_cast_or_null<MDNode>(DbgNode->getOperand(7));
+}
 
 //===----------------------------------------------------------------------===//
 // Predicates
diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index d427e287af8..30d63991ea0 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -1410,8 +1410,16 @@ DwarfDebug::collectVariableInfo(const MachineFunction *MF,
     if (DV.getTag() == dwarf::DW_TAG_arg_variable &&
         DISubprogram(DV.getContext()).describes(MF->getFunction()))
       Scope = CurrentFnDbgScope;
-    else
-      Scope = findDbgScope(MInsn->getDebugLoc());
+    else {
+      if (DV.getVersion() <= LLVMDebugVersion9)
+        Scope = findDbgScope(MInsn->getDebugLoc());
+      else {
+        if (MDNode *IA = DV.getInlinedAt())
+          Scope = InlinedDbgScopeMap.lookup(DebugLoc::getFromDILocation(IA));
+        else
+          Scope = DbgScopeMap.lookup(cast<MDNode>(DV->getOperand(1)));
+      }
+    }
     // If variable scope is not found then skip this variable.
     if (!Scope)
       continue;