De-virtualize GlobalValue

The erase/remove from parent methods now use a switch table to remove
themselves from their appropriate parent ilist.

The copyAttributesFrom method is now completely non-virtual, since we
only ever copy attributes from a global of the appropriate type.

Pre-requisite to de-virtualizing Value to save a vptr
(https://reviews.llvm.org/D31261).

NFC

llvm-svn: 302823

6 files changed, 26 insertions, 14 deletions

diff --git a/llvm/include/llvm/IR/Function.h b/llvm/include/llvm/IR/Function.h
index 4e4128138cb..8a2a6ed87eb 100644
--- a/llvm/include/llvm/IR/Function.h
+++ b/llvm/include/llvm/IR/Function.h
@@ -494,7 +494,7 @@ public:
 
   /// copyAttributesFrom - copy all additional attributes (those not needed to
   /// create a Function) from the Function Src to this one.
-  void copyAttributesFrom(const GlobalValue *Src) override;
+  void copyAttributesFrom(const Function *Src);
 
   /// deleteBody - This method deletes the body of the function, and converts
   /// the linkage to external.
@@ -507,12 +507,12 @@ public:
   /// removeFromParent - This method unlinks 'this' from the containing module,
   /// but does not delete it.
   ///
-  void removeFromParent() override;
+  void removeFromParent();
 
   /// eraseFromParent - This method unlinks 'this' from the containing module
   /// and deletes it.
   ///
-  void eraseFromParent() override;
+  void eraseFromParent();
 
   /// Steal arguments from another function.
   ///
diff --git a/llvm/include/llvm/IR/GlobalAlias.h b/llvm/include/llvm/IR/GlobalAlias.h
index 37a291dfeb7..d4bf0d7e1ed 100644
--- a/llvm/include/llvm/IR/GlobalAlias.h
+++ b/llvm/include/llvm/IR/GlobalAlias.h
@@ -59,15 +59,19 @@ public:
   // Linkage, Type, Parent and AddressSpace taken from the Aliasee.
   static GlobalAlias *create(const Twine &Name, GlobalValue *Aliasee);
 
+  void copyAttributesFrom(const GlobalValue *Src) {
+    GlobalValue::copyAttributesFrom(Src);
+  }
+
   /// removeFromParent - This method unlinks 'this' from the containing module,
   /// but does not delete it.
   ///
-  void removeFromParent() override;
+  void removeFromParent();
 
   /// eraseFromParent - This method unlinks 'this' from the containing module
   /// and deletes it.
   ///
-  void eraseFromParent() override;
+  void eraseFromParent();
 
   /// These methods retrieve and set alias target.
   void setAliasee(Constant *Aliasee);
diff --git a/llvm/include/llvm/IR/GlobalIFunc.h b/llvm/include/llvm/IR/GlobalIFunc.h
index bfaa9960cb1..d90c7c78ed2 100644
--- a/llvm/include/llvm/IR/GlobalIFunc.h
+++ b/llvm/include/llvm/IR/GlobalIFunc.h
@@ -47,12 +47,16 @@ public:
                              LinkageTypes Linkage, const Twine &Name,
                              Constant *Resolver, Module *Parent);
 
+  void copyAttributesFrom(const GlobalIFunc *Src) {
+    GlobalValue::copyAttributesFrom(Src);
+  }
+
   /// This method unlinks 'this' from the containing module, but does not
   /// delete it.
-  void removeFromParent() final;
+  void removeFromParent();
 
   /// This method unlinks 'this' from the containing module and deletes it.
-  void eraseFromParent() final;
+  void eraseFromParent();
 
   /// These methods retrieve and set ifunc resolver function.
   void setResolver(Constant *Resolver) {
diff --git a/llvm/include/llvm/IR/GlobalObject.h b/llvm/include/llvm/IR/GlobalObject.h
index f3789bafefe..fc38f698027 100644
--- a/llvm/include/llvm/IR/GlobalObject.h
+++ b/llvm/include/llvm/IR/GlobalObject.h
@@ -150,8 +150,10 @@ public:
 
   void addTypeMetadata(unsigned Offset, Metadata *TypeID);
 
-  void copyAttributesFrom(const GlobalValue *Src) override;
+protected:
+  void copyAttributesFrom(const GlobalObject *Src);
 
+public:
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static inline bool classof(const Value *V) {
     return V->getValueID() == Value::FunctionVal ||
diff --git a/llvm/include/llvm/IR/GlobalValue.h b/llvm/include/llvm/IR/GlobalValue.h
index bb30fa8be86..b595c225ce8 100644
--- a/llvm/include/llvm/IR/GlobalValue.h
+++ b/llvm/include/llvm/IR/GlobalValue.h
@@ -435,10 +435,12 @@ public:
 
   bool isWeakForLinker() const { return isWeakForLinker(getLinkage()); }
 
+protected:
   /// Copy all additional attributes (those not needed to create a GlobalValue)
   /// from the GlobalValue Src to this one.
-  virtual void copyAttributesFrom(const GlobalValue *Src);
+  void copyAttributesFrom(const GlobalValue *Src);
 
+public:
   /// If special LLVM prefix that is used to inform the asm printer to not emit
   /// usual symbol prefix before the symbol name is used then return linkage
   /// name after skipping this special LLVM prefix.
@@ -530,10 +532,10 @@ public:
 
   /// This method unlinks 'this' from the containing module, but does not delete
   /// it.
-  virtual void removeFromParent() = 0;
+  void removeFromParent();
 
   /// This method unlinks 'this' from the containing module and deletes it.
-  virtual void eraseFromParent() = 0;
+  void eraseFromParent();
 
   /// Get the module that this global value is contained inside of...
   Module *getParent() { return Parent; }
diff --git a/llvm/include/llvm/IR/GlobalVariable.h b/llvm/include/llvm/IR/GlobalVariable.h
index c25e08059ce..21d334c8f01 100644
--- a/llvm/include/llvm/IR/GlobalVariable.h
+++ b/llvm/include/llvm/IR/GlobalVariable.h
@@ -158,17 +158,17 @@ public:
 
   /// copyAttributesFrom - copy all additional attributes (those not needed to
   /// create a GlobalVariable) from the GlobalVariable Src to this one.
-  void copyAttributesFrom(const GlobalValue *Src) override;
+  void copyAttributesFrom(const GlobalVariable *Src);
 
   /// removeFromParent - This method unlinks 'this' from the containing module,
   /// but does not delete it.
   ///
-  void removeFromParent() override;
+  void removeFromParent();
 
   /// eraseFromParent - This method unlinks 'this' from the containing module
   /// and deletes it.
   ///
-  void eraseFromParent() override;
+  void eraseFromParent();
 
   /// Drop all references in preparation to destroy the GlobalVariable. This
   /// drops not only the reference to the initializer but also to any metadata.