title: SMT-LIB syntax for execution time
body: <p>I have been working on model generation problem on bit-vectors using SMT-LIB format. I want to know the execution time of my programs. 
  I could only found the below statement in the paper 
  ** "<a href="http://smtlib.cs.uiowa.edu/papers/smt-lib-reference-v2.5-r2015-06-28.pdf" rel="nofollow noreferrer">http://smtlib.cs.uiowa.edu/papers/smt-lib-reference-v2.5-r2015-06-28.pdf</a>"** </p>
  
  <p>Some commonly used statistics (e.g., number of restarts of a solver’s propositional reasoning engine) are difficult to define precisely and generally, while the exact semantics of others, such as time and memory
  usage, have not being agreed upon yet by the SMT-community.</p>
  
  <p>What is the SMT-syntax for execution time of a program? </p>