[clang] Clean up strange uses of getAnalysisIfAvailable (PR #65729)

[Björn Pettersson via cfe-commits]

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@@ -261,7 +261,7 @@ bool VirtRegRewriter::runOnMachineFunction(MachineFunction &fn) {
   Indexes = &getAnalysis<SlotIndexes>();
   LIS = &getAnalysis<LiveIntervals>();
   VRM = &getAnalysis<VirtRegMap>();
-  DebugVars = getAnalysisIfAvailable<LiveDebugVariables>();
+  DebugVars = &getAnalysis<LiveDebugVariables>();
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bjope wrote:

Not sure how to add a comment on line 278 if I want to suggest an edit on that line (in Phabricator it would have been easy). But I guess the check if DebugVars is null or not on line 278 is redundant now.

https://github.com/llvm/llvm-project/pull/65729