[llvm] [SPIR-V] Ensure that a correct pointer type is deduced from the Value argument of OpAtomic* instructions (PR #127492)

[Vyacheslav Levytskyy via llvm-commits]

================
@@ -934,9 +937,23 @@ bool SPIRVEmitIntrinsics::deduceOperandElementTypeCalledFunction(
       case SPIRV::OpAtomicUMax:
       case SPIRV::OpAtomicSMin:
       case SPIRV::OpAtomicSMax: {
-        KnownElemTy = getAtomicElemTy(GR, CI, Op);
+        KnownElemTy = isPointerTy(CI->getType()) ? getAtomicElemTy(GR, CI, Op)
+                                                 : CI->getType();
         if (!KnownElemTy)
           return true;
+        Uncomplete = isTodoType(Op);
+        Ops.push_back(std::make_pair(Op, 0));
+      } break;
+      case SPIRV::OpAtomicStore: {
+        if (CI->arg_size() < 4)
+          return true;
+        Value *ValOp = CI->getArgOperand(3);
+        KnownElemTy = isPointerTy(ValOp->getType())
+                          ? getAtomicElemTy(GR, CI, Op)
+                          : ValOp->getType();
+        if (!KnownElemTy)
+          return true;
+        Uncomplete = isTodoType(Op);
----------------
VyacheslavLevytskyy wrote:

It's the same patter as we see in deduceOperandElementType() - this variable means that a related pointer has the default type (i8) assigned rather than a deduced one, and we may change the type if we get a better type. It's in use actually, please see

```
      if (!Uncomplete)
        eraseTodoType(Op);
```

below the call to deduceOperandElementTypeCalledFunction().

https://github.com/llvm/llvm-project/pull/127492