Replace TargetInstrInfo::isInvariantLoad and its target-specific

implementations with a new MachineInstr::isInvariantLoad, which uses
MachineMemOperands and is target-independent. This brings MachineLICM
and other functionality to targets which previously lacked an
isInvariantLoad implementation.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83475 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/CodeGen/MachineInstr.h

@@ -26,6 +26,7 @@
 
 namespace llvm {
 
+class AliasAnalysis;
 class TargetInstrDesc;
 class TargetInstrInfo;
 class TargetRegisterInfo;
@@ -286,6 +287,13 @@ public:
   /// have no volatile memory references.
   bool hasVolatileMemoryRef() const;
 
+  /// isInvariantLoad - Return true if this instruction is loading from a
+  /// location whose value is invariant across the function.  For example,
+  /// loading a value from the constant pool or from from the argument area of
+  /// a function if it does not change.  This should only return true of *all*
+  /// loads the instruction does are invariant (if it does multiple loads).
+  bool isInvariantLoad(AliasAnalysis *AA = 0) const;
+
   //
   // Debugging support
   //