[clang] [llvm] [HLSL] Adding Flatten and Branch if attributes (PR #116331)

[Chris B via cfe-commits]

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@@ -300,6 +301,36 @@ static MDTuple *emitTopLevelLibraryNode(Module &M, MDNode *RMD,
   return constructEntryMetadata(nullptr, nullptr, RMD, Properties, Ctx);
 }
 
+// TODO: We might need to refactor this to be more generic,
+// in case we need more metadata to be replaced.
+static void translateBranchMetadata(Module &M) {
+  for (auto &F : M) {
+    for (auto &BB : F) {
+      auto *BBTerminatorInst = BB.getTerminator();
+
+      auto *HlslControlFlowMD =
+          BBTerminatorInst->getMetadata("hlsl.controlflow.hint");
+
+      if (!HlslControlFlowMD || HlslControlFlowMD->getNumOperands() < 2)
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llvm-beanz wrote:

Huh? `getMetadata` returns `null` on failure (hence the null check). If it finds the named metadata, it must have two operands right? You even have this asserting on the SPIR-V side.

https://github.com/llvm/llvm-project/pull/116331