Add a mechanism for invalidating the LiveOutInfo of a PHI, and use it whenever

[oota-llvm.git] / include / llvm / GlobalValue.h

diff --git a/include/llvm/GlobalValue.h b/include/llvm/GlobalValue.h
index 5132d395ef10f8f399f3b2a0ac983b05b81d8bd0..b184b8e449713fd2aa0246759dc049dda65caac5 100644 (file)
--- a/include/llvm/GlobalValue.h
+++ b/include/llvm/GlobalValue.h
@@ -39,8 +39,10 @@ public:
     AppendingLinkage,   ///< Special purpose, only applies to global arrays
     InternalLinkage,    ///< Rename collisions when linking (static functions).
     PrivateLinkage,     ///< Like Internal, but omit from symbol table.
-    LinkerPrivateLinkage, ///< Like private, but linker removes.
-    LinkerWeakLinkage,  ///< Like linker private, but weak.
+    LinkerPrivateLinkage, ///< Like Private, but linker removes.
+    LinkerPrivateWeakLinkage, ///< Like LinkerPrivate, but weak.
+    LinkerPrivateWeakDefAutoLinkage, ///< Like LinkerPrivateWeak, but possibly
+                                     ///  hidden.
     DLLImportLinkage,   ///< Function to be imported from DLL
     DLLExportLinkage,   ///< Function to be accessible from DLL.
     ExternalWeakLinkage,///< ExternalWeak linkage description.
@@ -58,7 +60,8 @@ protected:
   GlobalValue(const Type *ty, ValueTy vty, Use *Ops, unsigned NumOps,
               LinkageTypes linkage, const Twine &Name)
     : Constant(ty, vty, Ops, NumOps), Parent(0),
-      Linkage(linkage), Visibility(DefaultVisibility), Alignment(0) {
+      Linkage(linkage), Visibility(DefaultVisibility), Alignment(0),
+      UnnamedAddr(0) {
     setName(Name);
   }
 
@@ -68,17 +71,20 @@ protected:
   LinkageTypes Linkage : 5;   // The linkage of this global
   unsigned Visibility : 2;    // The visibility style of this global
   unsigned Alignment : 16;    // Alignment of this symbol, must be power of two
+  unsigned UnnamedAddr : 1;   // This value's address is not significant
   std::string Section;        // Section to emit this into, empty mean default
 public:
   ~GlobalValue() {
     removeDeadConstantUsers();   // remove any dead constants using this.
   }
 
-  unsigned getAlignment() const { return Alignment; }
-  void setAlignment(unsigned Align) {
-    assert((Align & (Align-1)) == 0 && "Alignment is not a power of 2!");
-    Alignment = Align;
+  unsigned getAlignment() const {
+    return (1u << Alignment) >> 1;
   }
+  void setAlignment(unsigned Align);
+
+  bool hasUnnamedAddr() const { return UnnamedAddr; }
+  void setUnnamedAddr(bool Val) { UnnamedAddr = Val; }
 
   VisibilityTypes getVisibility() const { return VisibilityTypes(Visibility); }
   bool hasDefaultVisibility() const { return Visibility == DefaultVisibility; }
@@ -135,12 +141,16 @@ public:
   static bool isLinkerPrivateLinkage(LinkageTypes Linkage) {
     return Linkage == LinkerPrivateLinkage;
   }
-  static bool isLinkerWeakLinkage(LinkageTypes Linkage) {
-    return Linkage == LinkerWeakLinkage;
+  static bool isLinkerPrivateWeakLinkage(LinkageTypes Linkage) {
+    return Linkage == LinkerPrivateWeakLinkage;
+  }
+  static bool isLinkerPrivateWeakDefAutoLinkage(LinkageTypes Linkage) {
+    return Linkage == LinkerPrivateWeakDefAutoLinkage;
   }
   static bool isLocalLinkage(LinkageTypes Linkage) {
     return isInternalLinkage(Linkage) || isPrivateLinkage(Linkage) ||
-      isLinkerPrivateLinkage(Linkage);
+      isLinkerPrivateLinkage(Linkage) || isLinkerPrivateWeakLinkage(Linkage) ||
+      isLinkerPrivateWeakDefAutoLinkage(Linkage);
   }
   static bool isDLLImportLinkage(LinkageTypes Linkage) {
     return Linkage == DLLImportLinkage;
@@ -159,22 +169,28 @@ public:
   /// by something non-equivalent at link time.  For example, if a function has
   /// weak linkage then the code defining it may be replaced by different code.
   static bool mayBeOverridden(LinkageTypes Linkage) {
-    return (Linkage == WeakAnyLinkage ||
-            Linkage == LinkOnceAnyLinkage ||
-            Linkage == CommonLinkage ||
-            Linkage == ExternalWeakLinkage);
+    return Linkage == WeakAnyLinkage ||
+           Linkage == LinkOnceAnyLinkage ||
+           Linkage == CommonLinkage ||
+           Linkage == ExternalWeakLinkage ||
+           Linkage == LinkerPrivateWeakLinkage ||
+           Linkage == LinkerPrivateWeakDefAutoLinkage;
   }
 
   /// isWeakForLinker - Whether the definition of this global may be replaced at
-  /// link time.
+  /// link time.  NB: Using this method outside of the code generators is almost
+  /// always a mistake: when working at the IR level use mayBeOverridden instead
+  /// as it knows about ODR semantics.
   static bool isWeakForLinker(LinkageTypes Linkage)  {
-    return (Linkage == AvailableExternallyLinkage ||
-            Linkage == WeakAnyLinkage ||
-            Linkage == WeakODRLinkage ||
-            Linkage == LinkOnceAnyLinkage ||
-            Linkage == LinkOnceODRLinkage ||
-            Linkage == CommonLinkage ||
-            Linkage == ExternalWeakLinkage);
+    return Linkage == AvailableExternallyLinkage ||
+           Linkage == WeakAnyLinkage ||
+           Linkage == WeakODRLinkage ||
+           Linkage == LinkOnceAnyLinkage ||
+           Linkage == LinkOnceODRLinkage ||
+           Linkage == CommonLinkage ||
+           Linkage == ExternalWeakLinkage ||
+           Linkage == LinkerPrivateWeakLinkage ||
+           Linkage == LinkerPrivateWeakDefAutoLinkage;
   }
 
   bool hasExternalLinkage() const { return isExternalLinkage(Linkage); }
@@ -191,7 +207,12 @@ public:
   bool hasInternalLinkage() const { return isInternalLinkage(Linkage); }
   bool hasPrivateLinkage() const { return isPrivateLinkage(Linkage); }
   bool hasLinkerPrivateLinkage() const { return isLinkerPrivateLinkage(Linkage); }
-  bool hasLinkerWeakLinkage() const { return isLinkerWeakLinkage(Linkage); }
+  bool hasLinkerPrivateWeakLinkage() const {
+    return isLinkerPrivateWeakLinkage(Linkage);
+  }
+  bool hasLinkerPrivateWeakDefAutoLinkage() const {
+    return isLinkerPrivateWeakDefAutoLinkage(Linkage);
+  }
   bool hasLocalLinkage() const { return isLocalLinkage(Linkage); }
   bool hasDLLImportLinkage() const { return isDLLImportLinkage(Linkage); }
   bool hasDLLExportLinkage() const { return isDLLExportLinkage(Linkage); }
@@ -261,12 +282,6 @@ public:
   inline Module *getParent() { return Parent; }
   inline const Module *getParent() const { return Parent; }
 
-  /// removeDeadConstantUsers - If there are any dead constant users dangling
-  /// off of this global value, remove them.  This method is useful for clients
-  /// that want to check to see if a global is unused, but don't want to deal
-  /// with potentially dead constants hanging off of the globals.
-  void removeDeadConstantUsers() const;
-
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static inline bool classof(const GlobalValue *) { return true; }
   static inline bool classof(const Value *V) {