[clang] [llvm] [ubsan] Parse and use <cutoffs[0,1,2]=70000;cutoffs[5,6,8]=90000> in LowerAllowCheckPass (PR #124211)

[Vitaly Buka via llvm-commits]

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@@ -828,11 +828,66 @@ parseLowerAllowCheckPassOptions(StringRef Params) {
     StringRef ParamName;
     std::tie(ParamName, Params) = Params.split(';');
 
-    return make_error<StringError>(
-        formatv("invalid LowerAllowCheck pass parameter '{0}' ", ParamName)
-            .str(),
-        inconvertibleErrorCode());
+    // Format is <cutoffs[1,2,3]=70000;cutoffs[5,6,8]=90000>
+    //
+    // Parsing allows duplicate indices (last one takes precedence).
+    // It would technically be in spec to specify
+    //   cutoffs[0]=70000,cutoffs[1]=90000,cutoffs[0]=80000,...
+    if (ParamName.starts_with("cutoffs[")) {
+      StringRef IndicesStr;
+      StringRef CutoffStr;
+
+      std::tie(IndicesStr, CutoffStr) = ParamName.split('=');
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vitalybuka wrote:

up to you, it's fine as is

https://github.com/llvm/llvm-project/pull/124211