[MLIR][SPIRV] Use getAsmResultName(...) hook for AddressOfOp.

[ergawy]

Summary

Implements better naming for results of spv.mlir.addressof ops by making it
inherit from OpAsmOpInterface and implementing the associated
getAsmResultName(...) hook.

mlir/include/mlir/Dialect/SPIRV/IR/SPIRVStructureOps.td

 include "mlir/Dialect/SPIRV/IR/SPIRVBase.td"
 include "mlir/IR/OpAsmInterface.td"
 include "mlir/IR/SymbolInterfaces.td"
 include "mlir/Interfaces/CallInterfaces.td"
 include "mlir/Interfaces/SideEffectInterfaces.td"
 
 // -----
 
-def SPV_AddressOfOp : SPV_Op<"mlir.addressof", [InFunctionScope, NoSideEffect]> {
+def SPV_AddressOfOp : SPV_Op<"mlir.addressof",
+    [DeclareOpInterfaceMethods<OpAsmOpInterface>, InFunctionScope, NoSideEffect]> {
   let summary = "Get the address of a global variable.";
 
   let description = [{
     Variables in module scope are defined using symbol names. This op generates
     an SSA value that can be used to refer to the symbol within function scope
     for use in ops that expect an SSA value. This operation has no corresponding
     SPIR-V instruction; it's merely used for modelling purpose in the SPIR-V
     dialect. Since variables in module scope in SPIR-V dialect are of pointer

mlir/lib/Dialect/SPIRV/IR/SPIRVOps.cpp

if (auto vecType = type.dyn_cast<VectorType>()) {
     if (elementType.isa<IntegerType>() || elementType.isa<FloatType>()) {
       specialName << "x" << elementType;
     }
   }
 
   setNameFn(getResult(), specialName.str());
 }
 
+void mlir::spirv::AddressOfOp::getAsmResultNames(
+    llvm::function_ref<void(mlir::Value, llvm::StringRef)> setNameFn) {
+  SmallString<32> specialNameBuffer;
+  llvm::raw_svector_ostream specialName(specialNameBuffer);
+  specialName << variable() << "_addr";
+  setNameFn(getResult(), specialName.str());
+}
+
 //===----------------------------------------------------------------------===//
 // spv.EntryPoint
 //===----------------------------------------------------------------------===//
 
 void spirv::EntryPointOp::build(OpBuilder &builder, OperationState &state,
                                 spirv::ExecutionModel executionModel,
                                 spirv::FuncOp function,
                                 ArrayRef<Attribute> interfaceVars) {

mlir/test/Dialect/SPIRV/IR/asm-op-interface.mlir

-// RUN: mlir-opt %s | FileCheck %s
+// RUN: mlir-opt %s -split-input-file | FileCheck %s
 
 func @const() -> () {
   // CHECK: %true
   %0 = spv.Constant true
   // CHECK: %false
   %1 = spv.Constant false
 
   // CHECK: %cst42_i32
func @const() -> () {
   // CHECK: %cst_vec_3xi32 
   %6 = spv.Constant dense<[1, 2, 3]> : vector<3xi32>
 
   // CHECK: %cst
   %8 = spv.Constant [dense<3.0> : vector<2xf32>] : !spv.array<1xvector<2xf32>>
 
   return
 }
+
+// -----
+
+spv.module Logical GLSL450 {
+  spv.GlobalVariable @global_var : !spv.ptr<f32, Input>
+
+  spv.func @addressof() -> () "None" {
+    // CHECK: %global_var_addr = spv.mlir.addressof 
+    %0 = spv.mlir.addressof @global_var : !spv.ptr<f32, Input>
+    spv.Return
+  }
+}
+