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Welcome to the Pycket wiki!

• The active development is on the master branch, check out the Readme file to get Pycket running.
• Also you want to get the latest Racket of course.
• The slack #pycket and irc #pycket are the best places to get help.

If you want to contribute, then let's go to the Pycket-Dev Page

Some Useful Readings

• Tracing the Meta-Level: PyPy’s Tracing JIT Compiler

• Chapters 5 and 6 of Antonio Cuni’s PhD thesis

JIT-Parameters and defaults

(Can be found in rpython/rlib/jit.py)

ENABLE_ALL_OPTS = (
    'intbounds:rewrite:virtualize:string:pure:earlyforce:heap:unroll')

PARAMETER_DOCS = {
    'threshold': 'number of times a loop has to run for it to become hot',
    'function_threshold': 'number of times a function must run for it to become traced from start',
    'trace_eagerness': 'number of times a guard has to fail before we start compiling a bridge',
    'decay': 'amount to regularly decay counters by (0=none, 1000=max)',
    'trace_limit': 'number of recorded operations before we abort tracing with ABORT_TOO_LONG',
    'inlining': 'inline python functions or not (1/0)',
    'loop_longevity': 'a parameter controlling how long loops will be kept before being freed, an estimate',
    'retrace_limit': 'how many times we can try retracing before giving up',
    'max_retrace_guards': 'number of extra guards a retrace can cause',
    'max_unroll_loops': 'number of extra unrollings a loop can cause',
    'disable_unrolling': 'after how many operations we should not unroll',
    'enable_opts': 'INTERNAL USE ONLY (MAY NOT WORK OR LEAD TO CRASHES): '
                   'optimizations to enable, or all = %s' % ENABLE_ALL_OPTS,
    'max_unroll_recursion': 'how many levels deep to unroll a recursive function',
    'vec': 'turn on the vectorization optimization (vecopt). ' \
           'Supports x86 (SSE 4.1), powerpc (SVX), s390x SIMD',
    'vec_cost': 'threshold for which traces to bail. Unpacking increases the counter,'\
                ' vector operation decrease the cost',
    'vec_all': 'try to vectorize trace loops that occur outside of the numpypy library',
}

PARAMETERS = {'threshold': 1039, # just above 1024, prime
              'function_threshold': 1619, # slightly more than one above, also prime
              'trace_eagerness': 200,
              'decay': 40,
              'trace_limit': 6000,
              'inlining': 1,
              'loop_longevity': 1000,
              'retrace_limit': 0,
              'max_retrace_guards': 15,
              'max_unroll_loops': 0,
              'disable_unrolling': 200,
              'enable_opts': 'all',
              'max_unroll_recursion': 7,
              'vec': 0,
              'vec_all': 0,
              'vec_cost': 0,
              }