Fix some problems with ASTCallbackVH in its use as a DenseMap key.

[oota-llvm.git] / lib / VMCore / Value.cpp

diff --git a/lib/VMCore/Value.cpp b/lib/VMCore/Value.cpp
index 1b9fe51332f49fc142cb5562e7b0022a01eb2e80..2cdd55217cc4133c1af6495513b7c0073e4db3aa 100644 (file)
--- a/lib/VMCore/Value.cpp
+++ b/lib/VMCore/Value.cpp
@@ -18,7 +18,7 @@
 #include "llvm/Instructions.h"
 #include "llvm/Operator.h"
 #include "llvm/Module.h"
-#include "llvm/MDNode.h"
+#include "llvm/Metadata.h"
 #include "llvm/ValueSymbolTable.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/Support/Debug.h"
@@ -142,6 +142,10 @@ static bool getSymTab(Value *V, ValueSymbolTable *&ST) {
   } else if (Argument *A = dyn_cast<Argument>(V)) {
     if (Function *P = A->getParent()) 
       ST = &P->getValueSymbolTable();
+  } else if (NamedMDNode *N = dyn_cast<NamedMDNode>(V)) {
+    if (Module *P = N->getParent()) {
+      ST = &P->getValueSymbolTable();
+    }
   } else if (isa<MDString>(V))
     return true;
   else {
@@ -151,33 +155,29 @@ static bool getSymTab(Value *V, ValueSymbolTable *&ST) {
   return false;
 }
 
-/// getNameStart - Return a pointer to a null terminated string for this name.
-/// Note that names can have null characters within the string as well as at
-/// their end.  This always returns a non-null pointer.
-const char *Value::getNameStart() const {
-  if (Name == 0) return "";
-  return Name->getKeyData();
-}
-
-/// getNameLen - Return the length of the string, correctly handling nul
-/// characters embedded into them.
-unsigned Value::getNameLen() const {
-  return Name ? Name->getKeyLength() : 0;
+StringRef Value::getName() const {
+  // Make sure the empty string is still a C string. For historical reasons,
+  // some clients want to call .data() on the result and expect it to be null
+  // terminated.
+  if (!Name) return StringRef("", 0);
+  return Name->getKey();
 }
 
-
 std::string Value::getNameStr() const {
   return getName().str();
 }
 
-void Value::setName(const Twine &Name) {
+void Value::setName(const Twine &NewName) {
   SmallString<32> NameData;
-  Name.toVector(NameData);
-  setName(NameData.begin(), NameData.size());
-}
+  NewName.toVector(NameData);
+
+  const char *NameStr = NameData.data();
+  unsigned NameLen = NameData.size();
+
+  // Name isn't changing?
+  if (getName() == StringRef(NameStr, NameLen))
+    return;
 
-void Value::setName(const char *NameStr, unsigned NameLen) {
-  if (NameLen == 0 && !hasName()) return;
   assert(getType() != Type::VoidTy && "Cannot assign a name to void values!");
   
   // Get the symbol table to update for this object.
@@ -193,13 +193,8 @@ void Value::setName(const char *NameStr, unsigned NameLen) {
       return;
     }
     
-    if (Name) {
-      // Name isn't changing?
-      if (NameLen == Name->getKeyLength() &&
-          !memcmp(Name->getKeyData(), NameStr, NameLen))
-        return;
+    if (Name)
       Name->Destroy();
-    }
     
     // NOTE: Could optimize for the case the name is shrinking to not deallocate
     // then reallocated.
@@ -213,11 +208,6 @@ void Value::setName(const char *NameStr, unsigned NameLen) {
   // NOTE: Could optimize for the case the name is shrinking to not deallocate
   // then reallocated.
   if (hasName()) {
-    // Name isn't changing?
-    if (NameLen == Name->getKeyLength() &&
-        !memcmp(Name->getKeyData(), NameStr, NameLen))
-      return;
-
     // Remove old name.
     ST->removeValueName(Name);
     Name->Destroy();
@@ -242,7 +232,7 @@ void Value::takeName(Value *V) {
     if (getSymTab(this, ST)) {
       // We can't set a name on this value, but we need to clear V's name if
       // it has one.
-      if (V->hasName()) V->setName(0, 0);
+      if (V->hasName()) V->setName("");
       return;  // Cannot set a name on this value (e.g. constant).
     }
     
@@ -262,7 +252,7 @@ void Value::takeName(Value *V) {
   if (!ST) {
     if (getSymTab(this, ST)) {
       // Clear V's name.
-      V->setName(0, 0);
+      V->setName("");
       return;  // Cannot set a name on this value (e.g. constant).
     }
   }