[llvm] [SPIRV] Lower load/store atomic to OpAtomicLoad/OpAtomicStore (PR #185696)

[Arseniy Obolenskiy via llvm-commits]

Juan Manuel Martinez =?utf-8?q?Caamaño?=,
Juan Manuel Martinez =?utf-8?q?Caamaño?=,
Juan Manuel Martinez =?utf-8?q?Caamaño?=,
Juan Manuel Martinez =?utf-8?q?Caamaño?Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/185696 at github.com>


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@@ -2018,23 +2068,67 @@ bool SPIRVInstructionSelector::selectStore(MachineInstr &I) const {
     }
   }
 
-  MachineBasicBlock &BB = *I.getParent();
-  auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpStore))
-                 .addUse(Ptr)
-                 .addUse(StoreVal);
+  if (I.getNumMemOperands()) {
+    const MachineMemOperand *MemOp = *I.memoperands_begin();
+    if (MemOp->isAtomic())
+      return selectAtomicStore(I);
+  }
+
+  MachineIRBuilder MIRBuilder(I);
+  auto MIB = MIRBuilder.buildInstr(SPIRV::OpStore).addUse(Ptr).addUse(StoreVal);
   if (!I.getNumMemOperands()) {
     assert(I.getOpcode() == TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS ||
            I.getOpcode() ==
                TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS);
     addMemoryOperands(I.getOperand(2 + OpOffset).getImm(), MIB);
   } else {
-    MachineIRBuilder MIRBuilder(I);
     addMemoryOperands(*I.memoperands_begin(), MIB, MIRBuilder, GR);
   }
   MIB.constrainAllUses(TII, TRI, RBI);
   return true;
 }
 
+bool SPIRVInstructionSelector::selectAtomicStore(MachineInstr &I) const {
+  LLVMContext &Context = I.getMF()->getFunction().getContext();
+
+  unsigned OpOffset = isa<GIntrinsic>(I) ? 1 : 0;
+  Register StoreVal = I.getOperand(0 + OpOffset).getReg();
+  Register Ptr = I.getOperand(1 + OpOffset).getReg();
+
+  SPIRVTypeInst PtrType = GR.getSPIRVTypeForVReg(Ptr);
+  SPIRVTypeInst PointeeType = GR.getPointeeType(PtrType);
+  if (!PointeeType.isTypeIntOrFloat())
+    return diagnoseUnsupported(I,
+                               "Lowering to SPIR-V of atomic store is only "
+                               "allowed for integer or floating point types");
+
+  const MachineMemOperand &MemOp = **I.memoperands_begin();
----------------
aobolensk wrote:

```suggestion

  assert(I.getNumMemOperands());
  const MachineMemOperand &MemOp = **I.memoperands_begin();
```

https://github.com/llvm/llvm-project/pull/185696