Package com.google.javascript.jscomp

Class DeadPropertyAssignmentElimination

java.lang.Object
com.google.javascript.jscomp.DeadPropertyAssignmentElimination
All Implemented Interfaces:
CompilerPass
public class DeadPropertyAssignmentElimination extends Object implements CompilerPass
An optimization pass that finds and removes dead property assignments within functions and classes.

This pass does not currently use the control-flow graph. It makes the following assumptions:

  • Functions with inner functions are not processed.
  • All properties are read whenever entering a block node. Dead assignments within a block are processed.
  • Hook nodes are not processed (it's assumed they read everything)
  • Switch blocks are not processed (it's assumed they read everything)
  • Any reference to a property getter/setter is treated like a call that escapes all props.
  • If there's an Object.definePropert{y,ies} call where the object or property name is aliased then the optimization does not run at all.
  • Properties names defined in externs will not be pruned.

  • Method Details

    • process

      public void process(Node externs, Node root)
      Description copied from interface: CompilerPass
      Process the JS with root node root. Can modify the contents of each Node tree
      Specified by:
      process in interface CompilerPass
      Parameters:
      externs - Top of external JS tree
      root - Top of JS tree