Update docs/DifferentiableProgrammingImplementation.md

Co-authored-by: Saleem Abdulrasool <[email protected]>

Author: philipturner

docs/DifferentiableProgrammingImplementation.md

@@ -468,7 +468,7 @@ bb0(%x):
 
 ### Visiting the original function to create a JVP
 
-In the Swift compiler, we have a class called [`JVPEmitter`](https://github.com/apple/swift/blob/main/lib/SILOptimizer/Mandatory/Differentiation.cpp) which subclasses [`TypeSubstCloner`](https://github.com/apple/swift/blob/master/include/swift/SIL/TypeSubstCloner.h). This uses the [visitor pattern](https://en.wikipedia.org/wiki/Visitor_pattern) to visit the original function and generate the JVP function. Taking a look at the `JVPEmitter` class, there are methods like `visitApplyInst`, `visitStructExtractInst`, etc. Each of these methods visit an instruction that is important in the generation of the JVP and differential, and emits a newly mapped version. We handle each type of instruction differently, explained below.
+In the Swift compiler, we have a class called [`JVPCloner`](https://github.com/apple/swift/blob/main/include/swift/SILOptimizer/Differentiation/JVPCloner.h) which subclasses [`TypeSubstCloner`](https://github.com/apple/swift/blob/master/include/swift/SIL/TypeSubstCloner.h). This uses the [visitor pattern](https://en.wikipedia.org/wiki/Visitor_pattern) to visit the original function and generate the JVP function. Taking a look at the `JVPCloner` class, there are methods like `visitApplyInst`, `visitStructExtractInst`, etc. Each of these methods visit an instruction that is important in the generation of the JVP and differential, and emits a newly mapped version. We handle each type of instruction differently, explained below.
 
 One important note is that in the JVP, we visit every single instruction in the original function - sometimes it’s an exact copy, and other times there is some special logic we wrote to handle it differently (e.g. like control-flow discussed below). This is so that the JVP function behaves just like the original function. With this, if the original function has a print statement, the JVP will as well. However, when we consider the differential, we will only transform SIL instructions from the original that we deem to be fit (so no print statement in the differential!). These instructions are those that should be differentiated, which uses the activity analysis calculated earlier to determine which SIL instructions are important in computing the tangent values of a function.