From 75549f4444cbb14e73c8f10ab90ec36c60413e8e Mon Sep 17 00:00:00 2001
From: Devang Patel <dpatel@apple.com>
Date: Thu, 1 Oct 2009 01:03:26 +0000
Subject: [PATCH] If location info is attached with an instruction then keep
 track of alloca slots used by a variable. This info will be used by
 AsmPrinter to emit debug info for variables.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83189 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/CodeGen/MachineModuleInfo.h | 14 ++++++++++++++
 lib/CodeGen/SelectionDAG/FastISel.cpp    | 12 +++++++++---
 2 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/include/llvm/CodeGen/MachineModuleInfo.h b/include/llvm/CodeGen/MachineModuleInfo.h
index 6707ab119c9..b7b90198b16 100644
--- a/include/llvm/CodeGen/MachineModuleInfo.h
+++ b/include/llvm/CodeGen/MachineModuleInfo.h
@@ -48,6 +48,7 @@ namespace llvm {
 //===----------------------------------------------------------------------===//
 // Forward declarations.
 class Constant;
+class MDNode;
 class GlobalVariable;
 class MachineBasicBlock;
 class MachineFunction;
@@ -142,9 +143,13 @@ class MachineModuleInfo : public ImmutablePass {
   /// DbgInfoAvailable - True if debugging information is available
   /// in this module.
   bool DbgInfoAvailable;
+
 public:
   static char ID; // Pass identification, replacement for typeid
 
+  typedef DenseMap<MDNode *, std::pair<MDNode *, unsigned> > VariableDbgInfoMapTy;
+  VariableDbgInfoMapTy VariableDbgInfo;
+
   MachineModuleInfo();
   ~MachineModuleInfo();
   
@@ -325,6 +330,15 @@ public:
   /// of one is required to emit exception handling info.
   Function *getPersonality() const;
 
+  /// setVariableDbgInfo - Collect information used to emit debugging information
+  /// of a variable.
+  void setVariableDbgInfo(MDNode *N, MDNode *L, unsigned S) {
+    if (N && L)
+      VariableDbgInfo[N] = std::make_pair(L, S);
+  }
+
+  VariableDbgInfoMapTy &getVariableDbgInfo() {  return VariableDbgInfo;  }
+
 }; // End class MachineModuleInfo
 
 } // End llvm namespace
diff --git a/lib/CodeGen/SelectionDAG/FastISel.cpp b/lib/CodeGen/SelectionDAG/FastISel.cpp
index 54544a4d149..0bec2cf9b1f 100644
--- a/lib/CodeGen/SelectionDAG/FastISel.cpp
+++ b/lib/CodeGen/SelectionDAG/FastISel.cpp
@@ -407,7 +407,6 @@ bool FastISel::SelectCall(User *I) {
         || !DW->ShouldEmitDwarfDebug())
       return true;
 
-    Value *Variable = DI->getVariable();
     Value *Address = DI->getAddress();
     if (BitCastInst *BCI = dyn_cast<BitCastInst>(Address))
       Address = BCI->getOperand(0);
@@ -418,8 +417,15 @@ bool FastISel::SelectCall(User *I) {
       StaticAllocaMap.find(AI);
     if (SI == StaticAllocaMap.end()) break; // VLAs.
     int FI = SI->second;
-    
-    DW->RecordVariable(cast<MDNode>(Variable), FI);
+    if (MMI) {
+      MetadataContext &TheMetadata = AI->getContext().getMetadata();
+      unsigned MDDbgKind = TheMetadata.getMDKind("dbg");
+      MDNode *AllocaLocation =
+        dyn_cast_or_null<MDNode>(TheMetadata.getMD(MDDbgKind, AI));
+      if (AllocaLocation)
+        MMI->setVariableDbgInfo(DI->getVariable(), AllocaLocation, FI);
+    }
+    DW->RecordVariable(DI->getVariable(), FI);
     return true;
   }
   case Intrinsic::eh_exception: {
-- 
2.34.1