[clang] [llvm] [polly] [NFC][DebugInfo] Use iterator moveBefore at many call-sites (PR #123583)

[Orlando Cazalet-Hyams via llvm-commits]

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@@ -448,7 +448,7 @@ void IRPromoter::ExtendSources() {
       if (isa<Argument>(V))
         I->moveBefore(InsertPt);
       else
-        I->moveAfter(InsertPt);
+        I->moveAfter(&*InsertPt);
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OCHyams wrote:

Same as earlier - is this a code-transition-state bug, or is there some reason we've got to use the `Instruction *` overload here? (this one matters more)

https://github.com/llvm/llvm-project/pull/123583