add a layer of accessors around the Value::SubClassData member, and use

a convention (shadowing the setter with private forwarding function) to
prevent subclasses from accidentally using it.

This exposed some bogosity in ConstantExprs, which was propaging the
opcode of the constant expr into the NUW/NSW/Exact field in the
getWithOperands/getWithOperandReplaced methods.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92239 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 13 insertions, 3 deletions

diff --git a/include/llvm/Function.h b/include/llvm/Function.h
index 64be545ba4..38822332c4 100644
--- a/include/llvm/Function.h
+++ b/include/llvm/Function.h
@@ -87,6 +87,9 @@ private:
   ValueSymbolTable *SymTab;               ///< Symbol table of args/instructions
   AttrListPtr AttributeList;              ///< Parameter attributes
 
+  // HasLazyArguments is stored in Value::SubclassData.
+  /*bool HasLazyArguments;*/
+                   
   // The Calling Convention is stored in Value::SubclassData.
   /*CallingConv::ID CallingConvention;*/
 
@@ -99,7 +102,7 @@ private:
   /// needs it.  The hasLazyArguments predicate returns true if the arg list
   /// hasn't been set up yet.
   bool hasLazyArguments() const {
-    return SubclassData & 1;
+    return getSubclassDataFromValue() & 1;
   }
   void CheckLazyArguments() const {
     if (hasLazyArguments())
@@ -156,10 +159,11 @@ public:
   /// calling convention of this function.  The enum values for the known
   /// calling conventions are defined in CallingConv.h.
   CallingConv::ID getCallingConv() const {
-    return static_cast<CallingConv::ID>(SubclassData >> 1);
+    return static_cast<CallingConv::ID>(getSubclassDataFromValue() >> 1);
   }
   void setCallingConv(CallingConv::ID CC) {
-    SubclassData = (SubclassData & 1) | (static_cast<unsigned>(CC) << 1);
+    setValueSubclassData((getSubclassDataFromValue() & 1) |
+                         (static_cast<unsigned>(CC) << 1));
   }
   
   /// getAttributes - Return the attribute list for this Function.
@@ -407,6 +411,12 @@ public:
   /// hasAddressTaken - returns true if there are any uses of this function
   /// other than direct calls or invokes to it.
   bool hasAddressTaken() const;
+private:
+  // Shadow Value::setValueSubclassData with a private forwarding method so that
+  // subclasses cannot accidentally use it.
+  void setValueSubclassData(unsigned short D) {
+    Value::setValueSubclassData(D);
+  }
 };
 
 inline ValueSymbolTable *