Re: [Chicken-janitors] #1620: Some let bindings are not replaced resulting in unnecessary CPS calls

[Chicken Trac]

#1620: Some let bindings are not replaced resulting in unnecessary CPS calls
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            Reporter:  sjamaan   |      Owner:
                Type:  defect    |     Status:  new
            Priority:  major     |  Milestone:  5.2
           Component:  compiler  |    Version:  5.0.0
          Resolution:            |   Keywords:
Estimated difficulty:  hard      |
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Comment (by sjamaan):

 Note: The `let` bindings are actually necessary when the arguments of `=`
 are impure; you want side-effects or exceptions to happen before calling
 `=`. The expanded generated code contains a shortcutting `C_and` call
 introduced by `fold-boolean` and each of the arguments except the first
 and the last are repeated twice, so if we got rid of the `let` completely,
 the resulting code would not be semantically equivalent.

 However, if they just alias other variables, I think they should always be
 replacable.

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Ticket URL: <https://bugs.call-cc.org/ticket/1620#comment:2>
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