[mlir][memref][spirv]: Address Feedback

* Remove use of initializer `if` statement to aid readability.
* Remove switch case macro and make statements explicit.

Signed-off-by: Jack Frankland <[email protected]>

Author: FranklandJack

mlir/lib/Conversion/MemRefToSPIRV/MemRefToSPIRV.cpp

@@ -715,9 +715,9 @@ ImageLoadOpPattern::matchAndRewrite(memref::LoadOp loadOp, OpAdaptor adaptor,
   // for plain images and the OpImageRead instruction needs to be materialized
   // instead or texels need to be accessed via atomics through a texel pointer.
   // Future work will generalize support to plain images.
-  if (auto convertedPointeeType = cast<spirv::PointerType>(
-          getTypeConverter()->convertType(loadOp.getMemRefType()));
-      !isa<spirv::SampledImageType>(convertedPointeeType.getPointeeType()))
+  auto convertedPointeeType = cast<spirv::PointerType>(
+      getTypeConverter()->convertType(loadOp.getMemRefType()));
+  if (!isa<spirv::SampledImageType>(convertedPointeeType.getPointeeType()))
     return rewriter.notifyMatchFailure(loadOp,
                                        "cannot lower memrefs which do not "
                                        "convert to SPIR-V sampled images");

mlir/lib/Dialect/SPIRV/Transforms/SPIRVConversion.cpp

@@ -588,17 +588,16 @@ static Type convertMemrefType(const spirv::TargetEnv &targetEnv,
     }
 
     const auto dim = [rank]() {
-#define DIM_CASE(DIM)                                                          \
-  case DIM:                                                                    \
-    return spirv::Dim::Dim##DIM##D
       switch (rank) {
-        DIM_CASE(1);
-        DIM_CASE(2);
-        DIM_CASE(3);
+      case 1:
+        return spirv::Dim::Dim1D;
+      case 2:
+        return spirv::Dim::Dim2D;
+      case 3:
+        return spirv::Dim::Dim3D;
       default:
         llvm_unreachable("Invalid memref rank!");
       }
-#undef DIM_CASE
     }();
 
     // Note that we currently only support lowering to single element texels