[clang] [llvm] [SPIRV][RFC] Rework / extend support for memory scopes (PR #106429)

[Vyacheslav Levytskyy via cfe-commits]

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@@ -58,7 +58,35 @@ class SPIRVTargetCodeGenInfo : public CommonSPIRTargetCodeGenInfo {
   SPIRVTargetCodeGenInfo(CodeGen::CodeGenTypes &CGT)
       : CommonSPIRTargetCodeGenInfo(std::make_unique<SPIRVABIInfo>(CGT)) {}
   void setCUDAKernelCallingConvention(const FunctionType *&FT) const override;
+  llvm::SyncScope::ID getLLVMSyncScopeID(const LangOptions &LangOpts,
+                                         SyncScope Scope,
+                                         llvm::AtomicOrdering Ordering,
+                                         llvm::LLVMContext &Ctx) const override;
 };
+
+inline StringRef mapClangSyncScopeToLLVM(SyncScope Scope) {
+  switch (Scope) {
+  case SyncScope::HIPSingleThread:
+  case SyncScope::SingleScope:
+    return "singlethread";
+  case SyncScope::HIPWavefront:
+  case SyncScope::OpenCLSubGroup:
+  case SyncScope::WavefrontScope:
+    return "subgroup";
+  case SyncScope::HIPWorkgroup:
+  case SyncScope::OpenCLWorkGroup:
+  case SyncScope::WorkgroupScope:
+    return "workgroup";
+  case SyncScope::HIPAgent:
+  case SyncScope::OpenCLDevice:
+  case SyncScope::DeviceScope:
+    return "device";
+  case SyncScope::SystemScope:
+  case SyncScope::HIPSystem:
+  case SyncScope::OpenCLAllSVMDevices:
+    return "";
+  }
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VyacheslavLevytskyy wrote:

I would opt for adding explicitly defined behavior at the end of the function (e.g., return "" as the fallback).

https://github.com/llvm/llvm-project/pull/106429