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[Chicken-janitors] #1619: Specialization ignores fixnum mode, leading to
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Chicken Trac |
Subject: |
[Chicken-janitors] #1619: Specialization ignores fixnum mode, leading to suboptimal code |
Date: |
Wed, 29 May 2019 14:33:06 -0000 |
#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?
--
Ticket URL: <https://bugs.call-cc.org/ticket/1619>
CHICKEN Scheme <https://www.call-cc.org/>
CHICKEN Scheme is a compiler for the Scheme programming language.
- [Chicken-janitors] #1619: Specialization ignores fixnum mode, leading to suboptimal code,
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