///
virtual bool pointsToConstantMemory(const Value *P) { return false; }
+ /// doesNotAccessMemory - If the specified function is known to never read or
+ /// write memory, return true.
+ ///
+ /// Many optimizations (such as CSE and LICM) can be performed on calls to it,
+ /// without worrying about aliasing properties, and many functions have this
+ /// property (e.g. 'sin' and 'cos').
+ ///
+ /// This property corresponds to the GCC 'const' attribute.
+ ///
+ virtual bool doesNotAccessMemory(Function *F) { return false; }
+
+ /// onlyReadsMemory - If the specified function is known to only read from
+ /// non-volatile memory (or not access memory at all), return true.
+ ///
+ /// This property allows many common optimizations to be performed in the
+ /// absence of interfering store instructions, such as CSE of strlen calls.
+ ///
+ /// This property corresponds to the GCC 'pure' attribute.
+ ///
+ virtual bool onlyReadsMemory(Function *F) { return doesNotAccessMemory(F); }
+
+
//===--------------------------------------------------------------------===//
/// Simple mod/ref information...
///