$b6d86a12 destructuring-no-base-identifier.js:1:1
  Registers: 14
  Blocks:    16
  Constants:
    [0] = Bool(false)
    [1] = Undefined
    [2] = Int32(1)
    [3] = Int32(2)

block0:
  [   0] GetLexicalEnvironment dst:reg4
  [   8] NewObject dst:reg5
  [  18] SetGlobal `x`, src:reg5
  [  28] NewPrimitiveArray dst:reg5, elements:[42]
  [  40] Mov dst:reg6, src:Bool(false)
  [  50] GetIterator dst_iterator_object:reg7, dst_iterator_next:reg8, dst_iterator_done:reg9, iterable:reg5
  [  68] Jump target:block3

block1:
  [  70] Catch dst:reg11
  [  78] SetLexicalEnvironment environment:reg4
  [  80] Mov dst:reg10, src:Int32(1)
  [  90] JumpIf condition:reg9, true_target:block11, false_target:block10

block2:
  [  a0] End value:reg5

block3:
  [  a8] GetGlobal dst:reg12, `x`
  [  b8] Jump target:block5

block4:
  [  c0] Mov dst:reg13, src:Undefined
  [  d0] Jump target:block6

block5:
  [  d8] IteratorNextUnpack dst_value:reg13, dst_done:reg6, iterator_object:reg7, iterator_next:reg8, iterator_done:reg9
  [  f0] JumpTrue condition:reg6, target:block4

block6:
  [ 100] PutById base:reg12, `y`, src:reg13, kind:Normal

block7:
  [ 120] JumpFalse condition:reg9, target:block9

block8:
  [ 130] End value:reg5

block9:
  [ 138] IteratorClose iterator_object:reg7, iterator_next:reg8, iterator_done:reg9, completion_value:Undefined
  [ 150] Jump target:block8

block10:
  [ 158] JumpStrictlyEquals lhs:reg10, rhs:Int32(1), true_target:block12, false_target:block13

block11:
  [ 170] JumpStrictlyEquals lhs:reg10, rhs:Int32(2), true_target:block14, false_target:block15

block12:
  [ 188] IteratorClose iterator_object:reg7, iterator_next:reg8, iterator_done:reg9, completion_value:reg11
  [ 1a0] Throw src:reg11

block13:
  [ 1a8] IteratorClose iterator_object:reg7, iterator_next:reg8, iterator_done:reg9, completion_value:Undefined
  [ 1c0] Jump target:block11

block14:
  [ 1c8] Return value:reg11

block15:
  [ 1d0] Throw src:reg11

Exception handlers:
  [  a8 ..   d8] => handler block1
  [ 100 ..  120] => handler block1