[llvm] [X86] Don't always seperate conditions in `(br (and/or cond0, cond1))` into seperate branches (PR #81689)

[Simon Pilgrim via llvm-commits]

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@@ -77,6 +81,24 @@ static cl::opt<int> ExperimentalPrefInnermostLoopAlignment(
         "alignment set by x86-experimental-pref-loop-alignment."),
     cl::Hidden);
 
+static cl::opt<int> BrMergingBaseCostThresh(
+    "x86-cond-base", cl::init(1),
+    cl::desc(
+        "Base."),
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RKSimon wrote:

Improve these descriptions

https://github.com/llvm/llvm-project/pull/81689