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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Also, the textual IR is really a developer/debugging tool, not something an end-user would be expected to look at, so the textual names would be largely pointless
in a release build.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">If you are writing lit tests that look at textual IR, and they are failing with release builds, you can add the "REQUIRES: asserts" directive to the lit test
so that the test won't be run for a release build.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">--paulr<o:p></o:p></span></p>
<p class="MsoNormal"><a name="_MailEndCompose"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D"><o:p> </o:p></span></a></p>
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<p class="MsoNormal"><b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> llvm-dev [mailto:llvm-dev-bounces@lists.llvm.org]
<b>On Behalf Of </b>Craig Topper via llvm-dev<br>
<b>Sent:</b> Wednesday, January 09, 2019 5:41 PM<br>
<b>To:</b> David Greene<br>
<b>Cc:</b> llvm-dev@lists.llvm.org<br>
<b>Subject:</b> Re: [llvm-dev] Textual IR value names<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">The names are dropped to save memory when a release build of the compiler is being used. This is what you probably want on a release compiler you intend to ship since it should be faster. The NDEBUG check is an easy way to tell the difference
between release and debug builds. People probably don't want to have to remember to set an additional cmake option to make a release compiler faster.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">The -fdiscard-value-names/-fno-discard-value-names was added about a year ago <a href="https://reviews.llvm.org/D42887">https://reviews.llvm.org/D42887</a> not sure if there is more discussion about the asserts behavior discussed there.<o:p></o:p></p>
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<o:p></o:p></p>
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<p class="MsoNormal">~Craig<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Wed, Jan 9, 2019 at 2:25 PM David Greene <<a href="mailto:dag@cray.com">dag@cray.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">Craig Topper via llvm-dev <<a href="mailto:llvm-dev@lists.llvm.org" target="_blank">llvm-dev@lists.llvm.org</a>> writes:<br>
<br>
> And the clang behavior can be controlled with -<br>
> fdiscard-value-names/-fno-discard-value-names<br>
<br>
That's a little better for users, but again, why should the default<br>
behavior change based on whether or not asserts are enabled?<br>
<br>
-David<o:p></o:p></p>
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