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

[Jorge Gorbe Moya 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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slackito wrote:

We still need something to hold the mapping between names and passes so we can dynamically create pass pipelines based on the flag value. Right now the PassRegistry is that something. What are you proposing exactly?

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