$49b95e06 annexb-function-existing-var.js:10:1
  Registers: 7
  Blocks:    1
  Constants:
    [0] = Undefined

block0:
  [   0] GetGlobal dst:reg6, `test`
  [  10] Call dst:reg5, callee:reg6, this_value:Undefined, test
  [  30] End value:reg5


test$02c02c04 annexb-function-existing-var.js:2:5
  Registers: 7
  Blocks:    1
  Constants:
    [0] = Undefined
    [1] = Int32(123)
    [2] = Bool(true)

block0:
  [   0] GetLexicalEnvironment dst:reg4
  [   8] CreateVariable `f`, is_immutable:false, is_global:false, is_strict:false
  [  18] InitializeVariableBinding `f`, src:Undefined
  [  30] SetLexicalBinding `f`, src:Int32(123)
  [  48] CreateLexicalEnvironment dst:reg5, parent:reg4, capacity:0, is_catch_environment:false
  [  60] CreateMutableBinding environment:reg5, `f`, can_be_deleted:false
  [  70] NewFunction dst:reg6, shared_function_data_index:0
  [  88] InitializeLexicalBinding `f`, src:reg6
  [  a0] GetBinding dst:reg6, `f`
  [  b8] SetVariableBinding `f`, src:reg6
  [  d0] SetLexicalEnvironment environment:reg4
  [  d8] GetInitializedBinding dst:reg5, `f`
  [  f0] Return value:reg5