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Hello Arnamoy,<br>
<br>
Thanks for your question. I think this is a question that you can ask during the Flang calls. I will share what I know, but this info might not be accurate.<br>
<br>
I am assuming that your question is about the non-I/O part of the flang runtime. The focus till a couple of months back was to get Flang/F18 working for F77. Since F77 does not have much of a runtime component there might not have been much thought gone into
sharing a design or keeping a public todo list for the runtime. <span style="font-family: "Segoe UI", "Segoe UI Web (West European)", "Segoe UI", -apple-system, system-ui, Roboto, "Helvetica Neue", sans-serif;"> </span></div>
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<br>
There was a lot of work that happened initially for the implementation of folding of intrinsics with constant inputs. You can see the implementation of these in the flang/lib/Evaluate directory. You can see some TODOs in the files in the Evaluate directory.
I think this is an area that you might be able to contribute to. Also see the following links.<br>
<a href="https://github.com/llvm/llvm-project/blob/main/flang/docs/Intrinsics.md" id="LPlnk">https://github.com/llvm/llvm-project/blob/main/flang/docs/Intrinsics.md</a><br>
<a href="https://github.com/llvm/llvm-project/blob/main/flang/docs/Intrinsics.md#intrinsic-functions-with-missing-folding-support" style="margin:0px;font-size:12pt;background-color:rgb(255, 255, 255)">https://github.com/llvm/llvm-project/blob/main/flang/docs/Intrinsics.md#intrinsic-functions-with-missing-folding-support</a><br>
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<span style="font-size: 12pt;">As of now, I am only aware of the date_and_time intrinsic which is implemented with a runtime function. You can see the implementation in the PR #412 (</span><a href="https://github.com/flang-compiler/f18-llvm-project/pull/412" style="font-size: 12pt;">https://github.com/flang-compiler/f18-llvm-project/pull/412</a><span style="font-size: 12pt;">)</span><span style="font-size: 12pt;">
in fir-dev branch. If you are interested in the runtime implementation, I believe you can take inspiration from the classic flang runtime (as hinted in </span><a href="https://github.com/flang-compiler/f18-llvm-project/pull/415#pullrequestreview-481755947" id="LPlnk317258" style="font-size: 12pt;">https://github.com/flang-compiler/f18-llvm-project/pull/415#pullrequestreview-481755947</a><span style="font-size: 12pt;">).
Since the array descriptors of classic flang and f18 are different there will be changes needed.</span><br>
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In general, I have often heard the following in relation to intrinsics/runtime. <br>
For math intrinsics, the plan is to use libpgmath. <br>
If llvm intrinsics are available, we will try to use that. <br>
The runtime should be kept free of other libraries.<br>
<span style="font-family:Calibri, Helvetica, sans-serif;background-color:rgb(255, 255, 255);display:inline !important"><br>
Jean Perier did much of the folding and the lowering/runtime work in fir-dev branch. He might know more. CCing
<a id="OWAAM815243" class="_1OtrSZdhKXVv3UhaivrdJ4 mention ms-bgc-nlr ms-fcl-b" href="mailto:jperier@nvidia.com">
@Jean Perier</a>.</span></font><br>
<br>
<font color="#000000" face="Calibri, Arial, Helvetica, sans-serif"><span style="font-size: 12pt;">Thanks,</span></font><br>
<font color="#000000" face="Calibri, Arial, Helvetica, sans-serif"><span style="font-size: 12pt;">Kiran</span></font></div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> flang-dev <flang-dev-bounces@lists.llvm.org> on behalf of Perry-Holby, Alexis via flang-dev <flang-dev@lists.llvm.org><br>
<b>Sent:</b> 27 January 2021 23:13<br>
<b>To:</b> Arnamoy Bhattacharyya <arnamoy@ualberta.ca>; flang-dev@lists.llvm.org <flang-dev@lists.llvm.org><br>
<b>Subject:</b> Re: [flang-dev] [EXTERNAL] Status of Flang runtime</font>
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<div class="PlainText">Hi Arnamoy,<br>
<br>
I'm not 100% certain what the status of the runtime is, but if you are looking for ways to contribute you can check out the issues list here:
<a href="https://github.com/flang-compiler/f18-llvm-project/issues">https://github.com/flang-compiler/f18-llvm-project/issues</a> . There are a couple that I see that have the "Runtime" label attached, which may be a good place to start.<br>
<br>
Thanks!<br>
Alexis Perry-Holby<br>
Los Alamos National Laboratory<br>
Applied Computer Science (CCS-7)<br>
<br>
On 1/9/21, 2:03 PM, "flang-dev on behalf of Arnamoy Bhattacharyya via flang-dev" <flang-dev-bounces@lists.llvm.org on behalf of flang-dev@lists.llvm.org> wrote:<br>
<br>
Hello all;<br>
<br>
I just wanted to ask what is the status of the flang runtime? I see a<br>
few commits from 5 days ago in fir-dev, but could not find any status<br>
tracking info or any milestones? Can anyone shed some light on what<br>
contribution areas are open in the runtime?<br>
<br>
Thank you very much.<br>
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