[llvm] [llvm-cov] Simplify and optimize MC/DC computation (PR #79727)

[Fangrui Song via llvm-commits]

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@@ -458,7 +395,7 @@ class MCDCRecordProcessor {
     MCDCRecord::TestVector TV(NumConditions, MCDCRecord::MCDC_DontCare);
 
     // Use the base test vector to build the list of all possible test vectors.
-    buildTestVector(TV);
+    buildTestVector(TV, 1, 0);
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MaskRay wrote:

If we use default arguments, they will only in this one call site. I think avoiding default arguments is at least equally readable:)

https://github.com/llvm/llvm-project/pull/79727