[Chicken-janitors] #1619: Specialization ignores fixnum mode, leading to suboptimal code

[Chicken Trac]

#1619: Specialization ignores fixnum mode, leading to suboptimal code
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 Reporter:  sjamaan   |                 Owner:
     Type:  defect    |                Status:  new
 Priority:  minor     |             Milestone:  5.2
Component:  compiler  |               Version:  5.0.0
 Keywords:            |  Estimated difficulty:
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 As we found with #1604, when running with `-fixnum-arithmetic`,
 specialization happens before optimization.

 Because the scrutinizer doesn't know about fixnum mode, this is still
 something of an issue, because we'd specialize to code that supports
 bignums, which is allocating. This is problematic in two ways: one is that
 the generated code that doesn't get replaced will not be able to deal with
 bignums (resulting in extremely strange behaviour on overflow or when the
 code results in ratnums), and it's less than optimal because fixnum ops
 aren't allocating, so they should be faster still.

 Perhaps we could stop the scrutinizer from doing replacements that deal
 with numerics in fixnum mode?

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Ticket URL: <https://bugs.call-cc.org/ticket/1619>
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