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<p class="MsoNormal"><span style="font-size:12.0pt">The FloatOut pass is designed so that it can do lambda lifting for every lambda. I think if you try<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt"> -ffloat-all-lams<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt">that might do it. See CoreMonad.FloatOutSwitches, the floatOutLambdas field<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt">Simon<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:12.0pt"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b><span lang="EN-US">From:</span></b><span lang="EN-US"> ghc-devs <ghc-devs-bounces@haskell.org>
<b>On Behalf Of </b>Csaba Hruska<br>
<b>Sent:</b> 10 April 2018 00:23<br>
<b>To:</b> ghc-devs@haskell.org<br>
<b>Subject:</b> GHC Core / STG to supercombinators<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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Hello,<br>
<br>
I'd like to use GHC as a haskell frontend in a project.<br>
I wonder what is the easiest way to compile Haskell to supercombinators (top level functions) using GHC as a library.<br>
<br>
Is it possible to use the simplifier to transform the parsed Haskell source to supercombinators? i.e. to do<o:p></o:p></p>
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eta expansion<o:p></o:p></li><li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo1">
closure conversion<o:p></o:p></li><li class="MsoNormal" style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo1">
lambda lifting<o:p></o:p></li></ul>
<p class="MsoNormal">Regarding the eta expansion and lambda lifting it seems (according the comments in simplifier code) it does not guarantee to make these transformations in every case.
<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">If GHC could transform the Core representation to supercombinators, which transformation should I use from
<b>CoreToDo</b>?<br>
<a href="https://na01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fghc%2Fghc%2Fblob%2Fmaster%2Fcompiler%2FsimplCore%2FCoreMonad.hs%23L107-L135&data=02%7C01%7Csimonpj%40microsoft.com%7C5add309622e243466e8d08d59e70eff6%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C636589130288505102&sdata=wzyODQuUBR9gkU0N39YRJLrmZhlXz4CLpNPyNHIFNDM%3D&reserved=0" target="_blank">https://github.com/ghc/ghc/blob/master/compiler/simplCore/CoreMonad.hs#L107-L135</a><o:p></o:p></p>
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<p class="MsoNormal">I'd like to use GHC as a frontend for my custom code generator which can handle (lazy) top level functions only.<o:p></o:p></p>
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<p class="MsoNormal">Is it better to use GHC as a library or is it better to write a compiler plugin to capture the core representation.<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">I do not want to optimize the Core at all neither want to use other parts of GHC's backend (i.e. codegen).<br>
Ideally GHC would typecheck and transform everything to top level function and my system would do the rest.<o:p></o:p></p>
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<p class="MsoNormal" style="margin-bottom:12.0pt">Do you know what would be the easiest way to do this? (i.e. via
<b>CoreToDo</b> or custom calls for the simplifying functions)<o:p></o:p></p>
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<p class="MsoNormal">Or would it be simpler to generate top level (lazy) functions from STG?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Regards,<o:p></o:p></p>
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<p class="MsoNormal">Csaba Hruska<o:p></o:p></p>
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