commit dd5eb023048d0ac69721eb919d3ef1bbaee2e1ce
author Bill Wendling <isanbard@gmail.com> Thu Dec 03 00:17:12 2009 +0000
committer Bill Wendling <isanbard@gmail.com> Thu Dec 03 00:17:12 2009 +0000
tree 2625a1251b0b0dc3c14d9b765055e01fb97197db
parent e731fa2957604b0a5d3964d927130ec58e457abe

This initial code is meant to convert TargetData to use an AbstractTypesUser so
that it doesn't have dangling pointers when abstract types are resolved. This
modifies it somewhat to address comments: making the "StructLayoutMap" an
anonymous structure, calling "removeAbstractTypeUser" when appropriate, and
adding asserts where helpful.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90362 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Target/TargetData.cpp

diff --git a/lib/Target/TargetData.cpp b/lib/Target/TargetData.cpp
index fc71bc3..ec00f9e 100644
--- a/lib/Target/TargetData.cpp
+++ b/lib/Target/TargetData.cpp
@@ -325,7 +325,7 @@
 
 typedef DenseMap<const StructType*, StructLayout*> LayoutInfoTy;
 
-namespace llvm {
+namespace {
 
 class StructLayoutMap : public AbstractTypeUser {
   LayoutInfoTy LayoutInfo;
@@ -337,18 +337,12 @@
   virtual void refineAbstractType(const DerivedType *OldTy,
                                   const Type *) {
     const StructType *STy = dyn_cast<const StructType>(OldTy);
-    if (!STy) {
-      OldTy->removeAbstractTypeUser(this);
-      return;
-    }
+    assert(STy && "This can only track struct types.");
 
-    StructLayout *SL = LayoutInfo[STy];
-    if (SL) {
-      SL->~StructLayout();
-      free(SL);
-      LayoutInfo[STy] = NULL;
-    }
-
+    LayoutInfoTy::iterator Iter = LayoutInfo.find(STy);
+    Iter->second->~StructLayout();
+    free(Iter->second);
+    LayoutInfo.erase(Iter);
     OldTy->removeAbstractTypeUser(this);
   }
 
@@ -359,69 +353,46 @@
   ///
   virtual void typeBecameConcrete(const DerivedType *AbsTy) {
     const StructType *STy = dyn_cast<const StructType>(AbsTy);
-    if (!STy) {
-      AbsTy->removeAbstractTypeUser(this);
-      return;
-    }
+    assert(STy && "This can only track struct types.");
 
-    StructLayout *SL = LayoutInfo[STy];
-    if (SL) {
-      SL->~StructLayout();
-      free(SL);
-      LayoutInfo[STy] = NULL;
-    }
-
+    LayoutInfoTy::iterator Iter = LayoutInfo.find(STy);
+    Iter->second->~StructLayout();
+    free(Iter->second);
+    LayoutInfo.erase(Iter);
     AbsTy->removeAbstractTypeUser(this);
   }
 
-  bool insert(const Type *Ty) {
-    if (Ty->isAbstract())
-      Ty->addAbstractTypeUser(this);
-    return true;
-  }
-
 public:
   virtual ~StructLayoutMap() {
     // Remove any layouts.
     for (LayoutInfoTy::iterator
-           I = LayoutInfo.begin(), E = LayoutInfo.end(); I != E; ++I)
-      if (StructLayout *SL = I->second) {
-        SL->~StructLayout();
-        free(SL);
+           I = LayoutInfo.begin(), E = LayoutInfo.end(); I != E; ++I) {
+      const Type *Key = I->first;
+      StructLayout *Value = I->second;
+
+      if (Key && Key->isAbstract())
+        Key->removeAbstractTypeUser(this);
+
+      if (Value) {
+        Value->~StructLayout();
+        free(Value);
       }
+    }
   }
 
-  inline LayoutInfoTy::iterator begin() {
-    return LayoutInfo.begin();
-  }
-  inline LayoutInfoTy::iterator end() {
-    return LayoutInfo.end();
-  }
-  inline LayoutInfoTy::const_iterator begin() const {
-    return LayoutInfo.begin();
-  }
-  inline LayoutInfoTy::const_iterator end() const {
+  LayoutInfoTy::iterator end() {
     return LayoutInfo.end();
   }
 
   LayoutInfoTy::iterator find(const StructType *&Val) {
     return LayoutInfo.find(Val);
   }
-  LayoutInfoTy::const_iterator find(const StructType *&Val) const {
-    return LayoutInfo.find(Val);
-  }
 
-  bool erase(const StructType *&Val) {
-    return LayoutInfo.erase(Val);
-  }
   bool erase(LayoutInfoTy::iterator I) {
     return LayoutInfo.erase(I);
   }
 
-  StructLayout *&operator[](const Type *Key) {
-    const StructType *STy = dyn_cast<const StructType>(Key);
-    assert(STy && "Trying to access the struct layout map with a non-struct!");
-    insert(STy);
+  StructLayout *&operator[](const StructType *STy) {
     return LayoutInfo[STy];
   }
 
@@ -432,14 +403,15 @@
 } // end namespace llvm
 
 TargetData::~TargetData() {
-  delete LayoutMap;
+  delete static_cast<StructLayoutMap*>(LayoutMap);
 }
 
 const StructLayout *TargetData::getStructLayout(const StructType *Ty) const {
   if (!LayoutMap)
     LayoutMap = new StructLayoutMap();
   
-  StructLayout *&SL = (*LayoutMap)[Ty];
+  StructLayoutMap *STM = static_cast<StructLayoutMap*>(LayoutMap);
+  StructLayout *&SL = (*STM)[Ty];
   if (SL) return SL;
 
   // Otherwise, create the struct layout.  Because it is variable length, we 
@@ -453,6 +425,10 @@
   SL = L;
   
   new (L) StructLayout(Ty, *this);
+
+  if (Ty->isAbstract())
+    Ty->addAbstractTypeUser(STM);
+
   return L;
 }
 
@@ -463,14 +439,17 @@
 void TargetData::InvalidateStructLayoutInfo(const StructType *Ty) const {
   if (!LayoutMap) return;  // No cache.
   
-  DenseMap<const StructType*, StructLayout*>::iterator I = LayoutMap->find(Ty);
-  if (I == LayoutMap->end()) return;
+  StructLayoutMap *STM = static_cast<StructLayoutMap*>(LayoutMap);
+  LayoutInfoTy::iterator I = STM->find(Ty);
+  if (I == STM->end()) return;
   
   I->second->~StructLayout();
   free(I->second);
-  LayoutMap->erase(I);
-}
+  STM->erase(I);
 
+  if (Ty->isAbstract())
+    Ty->removeAbstractTypeUser(STM);
+}
 
 std::string TargetData::getStringRepresentation() const {
   std::string Result;