[clang] [sanitizer] Refactor -f(no-)?sanitize-recover parsing (PR #119819)

[Vitaly Buka via cfe-commits]

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@@ -247,48 +247,72 @@ static SanitizerMask setGroupBits(SanitizerMask Kinds) {
   return Kinds;
 }
 
-// Computes the sanitizer mask based on the default plus opt-in (if supported)
-// minus opt-out.
+// Computes the sanitizer mask as:
+//     Default + AlwaysIn + Arguments - AlwaysOut
+// with arguments parsed from left to right.
+//
+// Error messages are optionally printed if the AlwaysIn or AlwaysOut
+// invariants are violated.
 static SanitizerMask
 parseSanitizeArgs(const Driver &D, const llvm::opt::ArgList &Args,
-                  bool DiagnoseErrors, SanitizerMask Supported,
-                  SanitizerMask Default, int OptInID, int OptOutID) {
-  SanitizerMask Remove; // During the loop below, the accumulated set of
-                        // sanitizers disabled by the current sanitizer
-                        // argument or any argument after it.
-  SanitizerMask Kinds;
-  SanitizerMask SupportedWithGroups = setGroupBits(Supported);
-
-  for (const llvm::opt::Arg *Arg : llvm::reverse(Args)) {
+                  bool DiagnoseErrors, SanitizerMask Default,
+                  SanitizerMask AlwaysIn, SanitizerMask AlwaysOut, int OptInID,
+                  int OptOutID) {
+
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vitalybuka wrote:

we may need asssert(AlwaysIn & AlwaysOut is empty)

https://github.com/llvm/llvm-project/pull/119819