Author: Maciej Fijalkowski <fij...@gmail.com> Branch: optresult-unroll Changeset: r79047:ccf6168de8e8 Date: 2015-08-19 11:09 +0200 http://bitbucket.org/pypy/pypy/changeset/ccf6168de8e8/
Log: some docs about unrolling diff --git a/rpython/jit/metainterp/optimizeopt/unrolling.rst b/rpython/jit/metainterp/optimizeopt/unrolling.rst new file mode 100644 --- /dev/null +++ b/rpython/jit/metainterp/optimizeopt/unrolling.rst @@ -0,0 +1,42 @@ + +nomenclature: + +Unrolling follows that order of operations: + +* optimize one version of a loop, call it <preamble>. At the end of <preamble>, + we gather virtual state by visiting the status of optimized boxes as + presented in the arguments to JUMP. Virtual state then can produce + a number of inputargs from a list + +* gather all the operations that can be produced in the short preamble. They're, + as far as I can tell: + + - jump arguments, as generated from the virtual state + + - pure operations, including pure calls + + - call_loopinvariant + + - heap cache + + or the combination of the above. Note that some operations can be produced + in more than one way. In those cases we keep both. + +* the optimizer state is influenced by replaying all the short boxes producing + operations. This populates the heap cache and the pure operation cache. + +* import the values of the inputargs (so e.g. constantness, intbounds, etc.) + +* we optimize normally, using extra boxes from the optimizer state + +* we import all the boxes that were not generated during this optimization + phase. This means, they have to: + + * be added to the start label + + * be added to the end jump + + * be added to the short preamble + +* we close the loop, which creates correct boxes in the jump (from virtualstate) + _______________________________________________ pypy-commit mailing list pypy-commit@python.org https://mail.python.org/mailman/listinfo/pypy-commit
