Class KotlinSafeCallOperatorFilter

java.lang.Object
org.jacoco.core.internal.analysis.filter.KotlinSafeCallOperatorFilter
All Implemented Interfaces:
IFilter
final class KotlinSafeCallOperatorFilter extends Object implements IFilter
Filters bytecode that Kotlin compiler generates for chains of safe call operators (?.).

  • Constructor Details

    • KotlinSafeCallOperatorFilter

      KotlinSafeCallOperatorFilter()

  • Method Details

    • filter

      public void filter(org.objectweb.asm.tree.MethodNode methodNode, IFilterContext context, IFilterOutput output)
      Description copied from interface: IFilter
      This method is called for every method. The filter implementation is expected to inspect the provided method and report its result to the given IFilterOutput instance.
      Specified by:
      filter in interface IFilter
      Parameters:
      methodNode - method to inspect
      context - context information for the method
      output - callback to report filtering results to

    • findChains

      private static Collection<ArrayList<org.objectweb.asm.tree.JumpInsnNode>> findChains(org.objectweb.asm.tree.MethodNode methodNode)
      "optimized" chain: 
      DUP
IFNULL label
... // call 0

...

DUP
IFNULL label
... // call N

label:
POP
      "unoptimized" chain: 
      ALOAD v0
IFNULL label
... // call 0

...

ASTORE v1
ALOAD v1
IFNULL label
... // call N

label:
ACONST_NULL
      "unoptimized" safe call operator(s) followed by elvis operator: 
      ALOAD v0
IFNULL nullCase
... // call 0

ASTORE v1
ALOAD v1
IFNULL nullCase
... // call 1

...

ASTORE vN
ALOAD vN
IFNULL nullCase
ALOAD vN
GOTO nonNullCase
nullCase:
... // right hand side of elvis operator
nonNullCase:
...

    • isUnoptimizedSafeCallFollowedByElvis

      private static boolean isUnoptimizedSafeCallFollowedByElvis(org.objectweb.asm.tree.JumpInsnNode jump, org.objectweb.asm.tree.AbstractInsnNode target, ArrayList<org.objectweb.asm.tree.JumpInsnNode> chain)

    • preceding

      private static org.objectweb.asm.tree.AbstractInsnNode preceding(org.objectweb.asm.tree.AbstractInsnNode i, int opcode)
      Returns:
      non pseudo-instruction preceding given if it has given opcode, null otherwise