From c04f46567c3ebf64257d8f03e29d80a69606a6bc Mon Sep 17 00:00:00 2001
From: Bill Wendling <isanbard@gmail.com>
Date: Thu, 3 Jul 2008 23:13:02 +0000
Subject: [PATCH] Don't return std::vector by value, but pass it in by
 reference to be filled.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53123 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/CodeGen/MachineModuleInfo.h | 15 +++++++--------
 lib/CodeGen/DwarfWriter.cpp              |  8 ++++----
 lib/CodeGen/MachineModuleInfo.cpp        | 22 ++++++++++------------
 3 files changed, 21 insertions(+), 24 deletions(-)

diff --git a/include/llvm/CodeGen/MachineModuleInfo.h b/include/llvm/CodeGen/MachineModuleInfo.h
index 54654fda5bd..a9567d2e255 100644
--- a/include/llvm/CodeGen/MachineModuleInfo.h
+++ b/include/llvm/CodeGen/MachineModuleInfo.h
@@ -1152,16 +1152,17 @@ public:
   
   /// getGlobalVariablesUsing - Return all of the GlobalVariables that use the
   /// named GlobalVariable.
-  std::vector<GlobalVariable*>
-  getGlobalVariablesUsing(Module &M, const std::string &RootName);
+  void getGlobalVariablesUsing(Module &M, const std::string &RootName,
+                               std::vector<GlobalVariable*> &Result);
 
   /// getAnchoredDescriptors - Return a vector of anchored debug descriptors.
   ///
-  template <class T>std::vector<T *> getAnchoredDescriptors(Module &M) {
+  template <class T>
+  void getAnchoredDescriptors(Module &M, std::vector<T*> &AnchoredDescs) {
     T Desc;
-    std::vector<GlobalVariable *> Globals =
-                             getGlobalVariablesUsing(M, Desc.getAnchorString());
-    std::vector<T *> AnchoredDescs;
+    std::vector<GlobalVariable *> Globals;
+    getGlobalVariablesUsing(M, Desc.getAnchorString(), Globals);
+
     for (unsigned i = 0, N = Globals.size(); i < N; ++i) {
       GlobalVariable *GV = Globals[i];
 
@@ -1171,8 +1172,6 @@ public:
         AnchoredDescs.push_back(cast<T>(DR.Deserialize(GV)));
       }
     }
-
-    return AnchoredDescs;
   }
   
   /// RecordRegionStart - Indicate the start of a region.
diff --git a/lib/CodeGen/DwarfWriter.cpp b/lib/CodeGen/DwarfWriter.cpp
index a284ba19eb6..2d0a1142027 100644
--- a/lib/CodeGen/DwarfWriter.cpp
+++ b/lib/CodeGen/DwarfWriter.cpp
@@ -2630,8 +2630,8 @@ private:
   /// ConstructGlobalDIEs - Create DIEs for each of the externally visible
   /// global variables.
   void ConstructGlobalDIEs() {
-    std::vector<GlobalVariableDesc *> GlobalVariables =
-        MMI->getAnchoredDescriptors<GlobalVariableDesc>(*M);
+    std::vector<GlobalVariableDesc *> GlobalVariables;
+    MMI->getAnchoredDescriptors<GlobalVariableDesc>(*M, GlobalVariables);
     
     for (unsigned i = 0, N = GlobalVariables.size(); i < N; ++i) {
       GlobalVariableDesc *GVD = GlobalVariables[i];
@@ -2642,8 +2642,8 @@ private:
   /// ConstructSubprogramDIEs - Create DIEs for each of the externally visible
   /// subprograms.
   void ConstructSubprogramDIEs() {
-    std::vector<SubprogramDesc *> Subprograms =
-        MMI->getAnchoredDescriptors<SubprogramDesc>(*M);
+    std::vector<SubprogramDesc *> Subprograms;
+    MMI->getAnchoredDescriptors<SubprogramDesc>(*M, Subprograms);
     
     for (unsigned i = 0, N = Subprograms.size(); i < N; ++i) {
       SubprogramDesc *SPD = Subprograms[i];
diff --git a/lib/CodeGen/MachineModuleInfo.cpp b/lib/CodeGen/MachineModuleInfo.cpp
index b33a2d3e369..3d3a9957bb0 100644
--- a/lib/CodeGen/MachineModuleInfo.cpp
+++ b/lib/CodeGen/MachineModuleInfo.cpp
@@ -52,10 +52,9 @@ getGlobalVariablesUsing(Value *V, std::vector<GlobalVariable*> &Result) {
 
 /// getGlobalVariablesUsing - Return all of the GlobalVariables that use the
 /// named GlobalVariable.
-static std::vector<GlobalVariable*>
-getGlobalVariablesUsing(Module &M, const std::string &RootName) {
-  std::vector<GlobalVariable*> Result;  // GlobalVariables matching criteria.
-  
+static void
+getGlobalVariablesUsing(Module &M, const std::string &RootName,
+                        std::vector<GlobalVariable*> &Result) {
   std::vector<const Type*> FieldTypes;
   FieldTypes.push_back(Type::Int32Ty);
   FieldTypes.push_back(Type::Int32Ty);
@@ -65,11 +64,8 @@ getGlobalVariablesUsing(Module &M, const std::string &RootName) {
                                                 StructType::get(FieldTypes));
 
   // If present and linkonce then scan for users.
-  if (UseRoot && UseRoot->hasLinkOnceLinkage()) {
+  if (UseRoot && UseRoot->hasLinkOnceLinkage())
     getGlobalVariablesUsing(UseRoot, Result);
-  }
-  
-  return Result;
 }
   
 /// isStringValue - Return true if the given value can be coerced to a string.
@@ -1593,7 +1589,8 @@ void MachineModuleInfo::AnalyzeModule(Module &M) {
 /// SetupCompileUnits - Set up the unique vector of compile units.
 ///
 void MachineModuleInfo::SetupCompileUnits(Module &M) {
-  std::vector<CompileUnitDesc *>CU = getAnchoredDescriptors<CompileUnitDesc>(M);
+  std::vector<CompileUnitDesc *> CU;
+  getAnchoredDescriptors<CompileUnitDesc>(M, CU);
   
   for (unsigned i = 0, N = CU.size(); i < N; i++) {
     CompileUnits.insert(CU[i]);
@@ -1608,10 +1605,11 @@ const UniqueVector<CompileUnitDesc *> MachineModuleInfo::getCompileUnits()const{
 
 /// getGlobalVariablesUsing - Return all of the GlobalVariables that use the
 /// named GlobalVariable.
-std::vector<GlobalVariable*>
+void
 MachineModuleInfo::getGlobalVariablesUsing(Module &M,
-                                           const std::string &RootName) {
-  return ::getGlobalVariablesUsing(M, RootName);
+                                           const std::string &RootName,
+                                           std::vector<GlobalVariable*>&Result){
+  return ::getGlobalVariablesUsing(M, RootName, Result);
 }
 
 /// RecordSourceLine - Records location information and associates it with a