[llvm] [SandboxVectorizer] Use sbvec-passes flag to create a pipeline of Region passes after BottomUpVec. (PR #111223)

[via llvm-commits]

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@@ -10,10 +10,69 @@
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/SandboxIR/Function.h"
 #include "llvm/SandboxIR/Instruction.h"
-
-using namespace llvm::sandboxir;
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Transforms/Vectorize/SandboxVectorizer/Passes/NullPass.h"
 
 namespace llvm::sandboxir {
+
+static cl::opt<bool>
+    PrintPassPipeline("sbvec-print-pass-pipeline", cl::init(false), cl::Hidden,
+                      cl::desc("Prints the pass pipeline and returns."));
+
+/// A magic string for the default pass pipeline.
+static const char *DefaultPipelineMagicStr = "*";
+
+static cl::opt<std::string> UserDefinedPassPipeline(
+    "sbvec-passes", cl::init(DefaultPipelineMagicStr), cl::Hidden,
+    cl::desc("Comma-separated list of vectorizer passes. If not set "
+             "we run the predefined pipeline."));
+
+static void registerAllRegionPasses(sandboxir::PassRegistry &PR) {
+  PR.registerPass(std::make_unique<sandboxir::NullPass>());
+}
+
+/// Adds to `RPM` a sequence of passes described by `Pipeline` from the `PR`
+/// pass registry.
+static void parseAndCreatePassPipeline(RegionPassManager &RPM, PassRegistry &PR,
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vporpo wrote:

Is this function going to be used for non RegionPasses too? If not, should it be a member function of RPM?

https://github.com/llvm/llvm-project/pull/111223