[llvm] [LoopIdiom] Use HashRecognize to optimize CRC (PR #143208)

[Ramkumar Ramachandra via llvm-commits]

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@@ -143,6 +144,14 @@ static cl::opt<bool, true>
                      cl::location(DisableLIRP::Wcslen), cl::init(false),
                      cl::ReallyHidden);
 
+bool DisableLIRP::HashRecognize;
+static cl::opt<bool, true>
+    DisableLIRPHashRecognize("disable-" DEBUG_TYPE "-hashrecognize",
+                             cl::desc("Proceed with loop idiom recognize pass, "
+                                      "but do not optimize CRC loops."),
+                             cl::location(DisableLIRP::HashRecognize),
+                             cl::init(false), cl::ReallyHidden);
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artagnon wrote:

Alright, everything seems to be in order: will merge. Quick note for reviewers in case regressions are found: prefer flipping this cl::init to true while the regression is being investigated, over reverting the patch.

https://github.com/llvm/llvm-project/pull/143208