Class EachElementHasNextInstruction


  • public class EachElementHasNextInstruction
    extends SSAAbstractBinaryInstruction
    This instruction represents iterating through the properties of its receiver object. The use represents an object, and the l-value represents a boolean indicating whether the object has more properties. Iterating across the fields or properties of a given object is a common idiom in scripting languages, which is why the IR has first-class support for it.
    • Constructor Detail

      • EachElementHasNextInstruction

        public EachElementHasNextInstruction​(int iindex,
                                             int lValue,
                                             int objectRef,
                                             int previousPropVal)
    • Method Detail

      • copyForSSA

        public SSAInstruction copyForSSA​(SSAInstructionFactory insts,
                                         int[] defs,
                                         int[] uses)
        Description copied from class: SSAInstruction
        This method is meant to be used during SSA conversion for an IR that is not in SSA form. It creates a new SSAInstruction of the same type as the receiver, with a combination of the receiver's uses and defs and those from the method parameters. In particular, if the 'defs' parameter is null, then the new instruction has the same defs as the receiver. If 'defs' is not null, it must be an array with a size equal to the number of defs that the receiver instruction has. In this case, the new instruction has defs taken from the array. The uses of the new instruction work in the same way with the 'uses' parameter. Note that this only applies to CAst-based IR translation, since Java bytecode-based IR generation uses a different SSA construction mechanism. TODO: move this into the SSAInstructionFactory
        Specified by:
        copyForSSA in class SSAInstruction
      • isFallThrough

        public boolean isFallThrough()
        Specified by:
        isFallThrough in class SSAInstruction
        Returns:
        true iff this instruction may fall through to the next