[llvm] [AMDGPU] NFC: Provide RPTracker interface for external iterators (PR #93088)

[Matt Arsenault via llvm-commits]

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@@ -317,14 +317,14 @@ getLanesWithProperty(const LiveIntervals &LIS, const MachineRegisterInfo &MRI,
     }
 
     return Result;
-  } else {
-    const LiveRange *LR = LIS.getCachedRegUnit(RegUnit);
-    // Be prepared for missing liveranges: We usually do not compute liveranges
-    // for physical registers on targets with many registers (GPUs).
-    if (LR == nullptr)
-      return SafeDefault;
-    return Property(*LR, Pos) ? LaneBitmask::getAll() : LaneBitmask::getNone();
   }
+
+  const LiveRange *LR = LIS.getCachedRegUnit(RegUnit);
+  // Be prepared for missing liveranges: We usually do not compute liveranges
+  // for physical registers on targets with many registers (GPUs).
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arsenm wrote:

This doesn't have anything to do with many registers or GPUs 

https://github.com/llvm/llvm-project/pull/93088