+ Use &TheUse = From->use_begin().getUse();
+ Instruction *User = cast<Instruction>(TheUse.getUser());
+ TheUse = To;
+
+ // Check to see if the instruction can be folded due to the operand
+ // replacement. For example changing (or X, Y) into (or X, -1) can replace
+ // the 'or' with -1.
+ Value *SimplifiedVal;
+ {
+ // Sanity check to make sure 'User' doesn't dangle across
+ // SimplifyInstruction.
+ AssertingVH<> UserHandle(User);