define: DUK_USE_VALSTACK_SHRINK_CHECK_SHIFT
introduced: 2.2.0
default: 2
tags:
  - performance
  - lowmemory
description: >
  When doing a value stack shrink check, skip shrinking if the difference
  between the minimum reserve and allocated size is less than
  (curr_size >> DUK_USE_VALSTACK_SHRINK_CHECK_SHIFT) bytes.  A value of 2
  means that the difference must be at least 25% for a shrink to happen.
  If undefined, value stack is always shrunk to the minimum reserved size
  with no slack.