[llvm] [SPIRV] Let atomic store store pointers (PR #201251)

[Nick Sarnie via llvm-commits]

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@@ -2073,12 +2073,50 @@ bool SPIRVInstructionSelector::selectAtomicStore(MachineInstr &I) const {
   Register MemSemReg = buildI32Constant(MemSem | StorageClass, I);
 
   MachineIRBuilder MIRBuilder(I);
-  auto AtomicStore = MIRBuilder.buildInstr(SPIRV::OpAtomicStore)
-                         .addUse(Ptr)
-                         .addUse(ScopeReg)
-                         .addUse(MemSemReg)
-                         .addUse(StoreVal);
-  AtomicStore.constrainAllUses(TII, TRI, RBI);
+
+  if (PointeeType.isTypePtr()) {
+    auto PtrSize = GR.getPointerSize();
+    SPIRVTypeInst SpirvType =
+        GR.getOrCreateSPIRVIntegerType(PtrSize, MIRBuilder);
+
+    Register NewVRegVal =
+        MRI->createGenericVirtualRegister(LLT::scalar(PtrSize));
+    MRI->setRegClass(NewVRegVal, MRI->getRegClassOrNull(StoreVal));
+    GR.assignSPIRVTypeToVReg(SpirvType, NewVRegVal, MIRBuilder.getMF());
+    MIRBuilder.buildInstr(SPIRV::OpConvertPtrToU)
+        .addDef(NewVRegVal)
+        .addUse(GR.getSPIRVTypeID(SpirvType)) // Result type
+        .addUse(StoreVal)                     // Pointer operand
+        .constrainAllUses(TII, TRI, RBI);
+
+    Register NewVRegPtr =
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sarnex wrote:

similar here, maybe something like `PtrCastedToMatchValReg` or something?

https://github.com/llvm/llvm-project/pull/201251