[llvm] [SPIR-V] Honor explicit memory_order/memory_scope in atomic load/store (PR #215572)

[Arseniy Obolenskiy via llvm-commits]

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@@ -635,24 +635,22 @@ static bool buildAtomicLoadInst(const SPIRV::IncomingCall *Call,
   if (Call->isSpirvOp())
     return buildOpFromWrapper(MIRBuilder, SPIRV::OpAtomicLoad, Call, TypeReg);
 
+  // atomic_load_explicit(ptr, memory_order[, memory_scope]).
   Register PtrRegister = Call->Arguments[0];
-  // TODO: if true insert call to __translate_ocl_memory_sccope before
-  // OpAtomicLoad and the function implementation. We can use Translator's
-  // output for transcoding/atomic_explicit_arguments.cl as an example.
+  MachineRegisterInfo *MRI = MIRBuilder.getMRI();
+
+  unsigned Semantics =
+      SPIRV::MemorySemantics::SequentiallyConsistent |
+      getMemSemanticsForStorageClass(GR->getPointerStorageClass(PtrRegister));
+  Register MemSemanticsReg =
+      Call->Arguments.size() >= 2 ? Call->Arguments[1] : Register();
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aobolensk wrote:

Done. Split it into computeMemSemantics and buildMemSemanticsReg

https://github.com/llvm/llvm-project/pull/215572