[llvm] [SandboxVec] Add pass to create Regions from metadata. Generalize SandboxVec pass pipelines. (PR #112288)

[via llvm-commits]

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@@ -14,9 +14,19 @@
 // NOTE: NO INCLUDE GUARD DESIRED!
 
 #ifndef REGION_PASS
-#define REGION_PASS(NAME, CREATE_PASS)
+#define REGION_PASS(NAME, CLASS_NAME)
 #endif
 
-REGION_PASS("null", NullPass())
+REGION_PASS("null", ::llvm::sandboxir::NullPass)
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vporpo wrote:

Why do we need to specify the namespace `::llvm::sandboxir::` here?

https://github.com/llvm/llvm-project/pull/112288