[llvm] [ARM] Apply sign-return-address attribute to outlined function (PR #107877)

[Benson Chu via llvm-commits]

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@@ -6623,10 +6626,8 @@ void ARMBaseInstrInfo::buildOutlinedFrame(
       MBB.addLiveIn(ARM::LR);
 
     // Insert a save before the outlined region
-    bool Auth = OF.Candidates.front()
-                    .getMF()
-                    ->getInfo<ARMFunctionInfo>()
-                    ->shouldSignReturnAddress(true);
+    bool Auth = MF.getInfo<ARMFunctionInfo>()
+                 ->shouldSignReturnAddress(true);
     saveLROnStack(MBB, It, true, Auth);
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pestctrl wrote:

This is a largely NFC change, but it makes the usage of saveLROnStack more consistent between `insertOutlinedCall` and `buildOutlinedFrame`. 

Both `insertOutlinedCall` and `buildOutlinedFrame` can query `MF` for `shouldSignReturnAddress`, instead of `buildOutlinedFrame` grabbing the front candidate. 

https://github.com/llvm/llvm-project/pull/107877