[llvm] [LLVM] Add a C API for creating instructions with custom syncscopes. (PR #104775)

[Tim Besard via llvm-commits]

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@@ -754,7 +755,13 @@ struct FunCloner {
         LLVMSetAlignment(Dst, LLVMGetAlignment(Src));
         LLVMSetOrdering(Dst, LLVMGetOrdering(Src));
         LLVMSetVolatile(Dst, LLVMGetVolatile(Src));
-        LLVMSetAtomicSingleThread(Dst, LLVMIsAtomicSingleThread(Src));
+        if (LLVMIsAtomic(Src)) {
+          LLVMBool IsAtomicSingleThread = LLVMIsAtomicSingleThread(Src);
+          if (IsAtomicSingleThread)
+            LLVMSetAtomicSingleThread(Dst, IsAtomicSingleThread);
+          else
+            LLVMSetAtomicSyncScopeID(Dst, LLVMGetAtomicSyncScopeID(Src));
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maleadt wrote:

Yeah, the intention was test coverage. I'll move it to a unit test.

https://github.com/llvm/llvm-project/pull/104775