[llvm] [SimplifyCFG] Consider preds to switch in `simplifyDuplicateSwitchArms` (PR #118955)

[Antonio Frighetto via llvm-commits]

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@@ -340,15 +340,23 @@ entry:
   i32 3, label %sw.bb3
   ]
 
-sw.bb: br label %if.end
-sw.bb1: br label %if.end
-sw.bb2: br label %if.end
-sw.bb3: br label %if.end
-sw.default: br label %if.end
-if.else: br label %if.end
+sw.bb:                                            ; preds = %entry, %entry
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antoniofrighetto wrote:

I took the chance to regenerate the test too, as the `if.else` branch was dead.

https://github.com/llvm/llvm-project/pull/118955