Add new ExecutionEngine::getGlobalValueAtAddress method, which can efficiently

turn a memory address back into the LLVM global object that starts at that
address.  Note that this won't cause any additional datastructures to be built
for clients of the EE that don't need this information.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10673 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/ExecutionEngine/ExecutionEngine.h b/include/llvm/ExecutionEngine/ExecutionEngine.h
index cf010084b70a78414a3ec128eb1c9f798381c631..2e4b3deda6ac5ae9aa6684fead278676fd4c7ad9 100644 (file)
--- a/include/llvm/ExecutionEngine/ExecutionEngine.h
+++ b/include/llvm/ExecutionEngine/ExecutionEngine.h
@@ -36,9 +36,15 @@ class ExecutionEngine {
   Module &CurMod;
   const TargetData *TD;
 
   Module &CurMod;
   const TargetData *TD;
 

-  // GlobalAddress - A mapping between LLVM global values and their actualized
-  // version...
-  std::map<const GlobalValue*, void *> GlobalAddress;
+  /// GlobalAddressMap - A mapping between LLVM global values and their
+  /// actualized version...
+  std::map<const GlobalValue*, void *> GlobalAddressMap;
+
+  /// GlobalAddressReverseMap - This is the reverse mapping of GlobalAddressMap,
+  /// used to convert raw addresses into the LLVM global value that is emitted
+  /// at the address.  This map is not computed unless getGlobalValueAtAddress
+  /// is called at some point.
+  std::map<void *, const GlobalValue*> GlobalAddressReverseMap;

 protected:
   ModuleProvider *MP;
 
 protected:
   ModuleProvider *MP;
 


@@ -74,17 +80,24 @@ public:
 
 
   void addGlobalMapping(const GlobalValue *GV, void *Addr) {
 
 
   void addGlobalMapping(const GlobalValue *GV, void *Addr) {

-    void *&CurVal = GlobalAddress[GV];
+    void *&CurVal = GlobalAddressMap[GV];

     assert((CurVal == 0 || Addr == 0) && "GlobalMapping already established!");
     CurVal = Addr;
     assert((CurVal == 0 || Addr == 0) && "GlobalMapping already established!");
     CurVal = Addr;

+
+    // If we are using the reverse mapping, add it too
+    if (!GlobalAddressReverseMap.empty()) {
+      const GlobalValue *&V = GlobalAddressReverseMap[Addr];
+      assert((V == 0 || GV == 0) && "GlobalMapping already established!");
+      V = GV;
+    }

   }
 
   /// getPointerToGlobalIfAvailable - This returns the address of the specified
   /// global value if it is available, otherwise it returns null.
   ///
   void *getPointerToGlobalIfAvailable(const GlobalValue *GV) {
   }
 
   /// getPointerToGlobalIfAvailable - This returns the address of the specified
   /// global value if it is available, otherwise it returns null.
   ///
   void *getPointerToGlobalIfAvailable(const GlobalValue *GV) {

-    std::map<const GlobalValue*, void*>::iterator I = GlobalAddress.find(GV);
-    return I != GlobalAddress.end() ? I->second : 0;
+    std::map<const GlobalValue*, void*>::iterator I = GlobalAddressMap.find(GV);
+    return I != GlobalAddressMap.end() ? I->second : 0;

   }
 
   /// getPointerToGlobal - This returns the address of the specified global
   }
 
   /// getPointerToGlobal - This returns the address of the specified global


@@ -107,6 +120,12 @@ public:
     return getPointerToFunction(F);
   }
 
     return getPointerToFunction(F);
   }
 

+  /// getGlobalValueAtAddress - Return the LLVM global value object that starts
+  /// at the specified address.
+  ///
+  const GlobalValue *getGlobalValueAtAddress(void *Addr);
+
+

   void StoreValueToMemory(GenericValue Val, GenericValue *Ptr, const Type *Ty);
   void InitializeMemory(const Constant *Init, void *Addr);
 
   void StoreValueToMemory(GenericValue Val, GenericValue *Ptr, const Type *Ty);
   void InitializeMemory(const Constant *Init, void *Addr);