[CIR] Lower to MLIR struct with array member

Do not go through a memref of memref.

Author: keryell

clang/lib/CIR/Lowering/ThroughMLIR/LowerCIRToMLIR.cpp

@@ -339,7 +339,13 @@ class CIRGetMemberOpLowering
         mlir::cast<mlir::named_tuple::NamedTupleType>(memref.getElementType());
     // The lowered type of the element to access in the named_tuple.
     auto loweredMemberType = namedTupleType.getType(memberIndex);
-    auto elementMemRefTy = mlir::MemRefType::get({}, loweredMemberType);
+    // memref.view can only cast to another memref. Wrap the target type if it
+    // is not already a memref (like with a struct with an array member)
+    mlir::MemRefType elementMemRefTy;
+    if (mlir::isa<mlir::MemRefType>(loweredMemberType))
+      elementMemRefTy = mlir::cast<mlir::MemRefType>(loweredMemberType);
+    else
+      elementMemRefTy = mlir::MemRefType::get({}, loweredMemberType);
     auto offset = structLayout->getElementOffset(memberIndex);
     // Synthesize the byte access to right lowered type.
     auto byteShift =
@@ -1368,7 +1374,7 @@ class CIRPtrStrideOpLowering
 
   // Return true if all the PtrStrideOp users are load, store or cast
   // with array_to_ptrdecay kind and they are in the same block.
-  inline bool isLoadStoreOrCastArrayToPtrProduer(cir::PtrStrideOp op) const {
+  inline bool isLoadStoreOrCastArrayToPtrProducer(cir::PtrStrideOp op) const {
     if (op.use_empty())
       return false;
     for (auto *user : op->getUsers()) {

clang/test/CIR/Lowering/ThroughMLIR/struct.cpp

@@ -1,40 +1,52 @@
 // RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -fno-clangir-direct-lowering -emit-mlir %s -o %t.mlir
 // RUN: FileCheck --input-file=%t.mlir %s
 
+// Check the MLIR lowering of struct and member accesses
 struct s {
   int a;
   double b;
   char c;
+  float d[5];
 };
 
 int main() {
   s v;
-  // CHECK: %[[ALLOCA:.+]] = memref.alloca() {alignment = 8 : i64} : memref<!named_tuple.named_tuple<"s", [i32, f64, i8]>>
+  // CHECK: %[[ALLOCA:.+]] = memref.alloca() {alignment = 8 : i64} : memref<!named_tuple.named_tuple<"s", [i32, f64, i8, memref<5xf32>]>>
   v.a = 7;
   // CHECK: %[[C_7:.+]] = arith.constant 7 : i32
-  // CHECK: %[[I8_EQUIV_A:.+]] = named_tuple.cast %[[ALLOCA]] : memref<!named_tuple.named_tuple<"s", [i32, f64, i8]>> to memref<24xi8>
+  // CHECK: %[[I8_EQUIV_A:.+]] = named_tuple.cast %[[ALLOCA]] : memref<!named_tuple.named_tuple<"s", [i32, f64, i8, memref<5xf32>]>> to memref<40xi8>
   // CHECK: %[[OFFSET_A:.+]] = arith.constant 0 : index
-  // CHECK: %[[VIEW_A:.+]] = memref.view %[[I8_EQUIV_A]][%[[OFFSET_A]]][] : memref<24xi8> to memref<i32>
+  // CHECK: %[[VIEW_A:.+]] = memref.view %[[I8_EQUIV_A]][%[[OFFSET_A]]][] : memref<40xi8> to memref<i32>
   // CHECK: memref.store %[[C_7]], %[[VIEW_A]][] : memref<i32>
 
   v.b = 3.;
   // CHECK: %[[C_3:.+]] = arith.constant 3.000000e+00 : f64
-  // CHECK: %[[I8_EQUIV_B:.+]] = named_tuple.cast %[[ALLOCA]] : memref<!named_tuple.named_tuple<"s", [i32, f64, i8]>> to memref<24xi8>
+  // CHECK: %[[I8_EQUIV_B:.+]] = named_tuple.cast %[[ALLOCA]] : memref<!named_tuple.named_tuple<"s", [i32, f64, i8, memref<5xf32>]>> to memref<40xi8>
   // CHECK: %[[OFFSET_B:.+]] = arith.constant 8 : index
-  // CHECK: %[[VIEW_B:.+]] = memref.view %[[I8_EQUIV_B]][%[[OFFSET_B]]][] : memref<24xi8> to memref<f64>
+  // CHECK: %[[VIEW_B:.+]] = memref.view %[[I8_EQUIV_B]][%[[OFFSET_B]]][] : memref<40xi8> to memref<f64>
   // CHECK: memref.store %[[C_3]], %[[VIEW_B]][] : memref<f64>
 
   v.c = 'z';
-  // CHECK: %[[C_122:.+]]  = arith.constant 122 : i8
-  // CHECK: %[[I8_EQUIV_C:.+]] = named_tuple.cast %[[ALLOCA]] : memref<!named_tuple.named_tuple<"s", [i32, f64, i8]>> to memref<24xi8>
+  // CHECK: %[[C_122:.+]] = arith.constant 122 : i8
+  // CHECK: %[[I8_EQUIV_C:.+]] = named_tuple.cast %[[ALLOCA]] : memref<!named_tuple.named_tuple<"s", [i32, f64, i8, memref<5xf32>]>> to memref<40xi8>
   // CHECK: %[[OFFSET_C:.+]] = arith.constant 16 : index
-  // CHECK: %[[VIEW_C:.+]] = memref.view %[[I8_EQUIV_C]][%[[OFFSET_C]]][] : memref<24xi8> to memref<i8>
+  // CHECK: %[[VIEW_C:.+]] = memref.view %[[I8_EQUIV_C]][%[[OFFSET_C]]][] : memref<40xi8> to memref<i8>
   // memref.store %[[C_122]], %[[VIEW_C]][] : memref<i8>
 
+  v.d[4] = 6.f;
+  // CHECK: %[[C_6:.+]] = arith.constant 6.000000e+00 : f32
+  // CHECK: %[[I8_EQUIV_D:.+]] = named_tuple.cast %alloca_0 : memref<!named_tuple.named_tuple<"s", [i32, f64, i8, memref<5xf32>]>> to memref<40xi8>
+  // CHECK: %[[OFFSET_D:.+]] = arith.constant 20 : index
+  // Do not lower to a memref of memref
+  // CHECK: %[[VIEW_D:.+]] = memref.view %3[%c20][] : memref<40xi8> to memref<5xf32>
+  // CHECK: %[[C_4:.+]] = arith.constant 4 : i32
+  // CHECK: %[[I_D:.+]] = arith.index_cast %[[C_4]] : i32 to index
+  // CHECK: memref.store %[[C_6]], %[[VIEW_D]][%[[I_D]]] : memref<5xf32>
+
   return v.c;
-  // CHECK: %[[I8_EQUIV_C_1:.+]] = named_tuple.cast %[[ALLOCA]] : memref<!named_tuple.named_tuple<"s", [i32, f64, i8]>> to memref<24xi8>
+  // CHECK: %[[I8_EQUIV_C_1:.+]] = named_tuple.cast %[[ALLOCA]] : memref<!named_tuple.named_tuple<"s", [i32, f64, i8, memref<5xf32>]>> to memref<40xi8>
   // CHECK: %[[OFFSET_C_1:.+]] = arith.constant 16 : index
-  // CHECK: %[[VIEW_C_1:.+]] = memref.view %[[I8_EQUIV_C_1]][%[[OFFSET_C_1]]][] : memref<24xi8> to memref<i8>
+  // CHECK: %[[VIEW_C_1:.+]] = memref.view %[[I8_EQUIV_C_1]][%[[OFFSET_C_1]]][] : memref<40xi8> to memref<i8>
   // CHECK: %[[VALUE_C:.+]] = memref.load %[[VIEW_C_1]][] : memref<i8>
   // CHECK: %[[VALUE_RET:.+]] = arith.extsi %[[VALUE_C]] : i8 to i32
  }

mlir/include/mlir/Dialect/NamedTuple/IR/NamedTupleDialect.h

@@ -17,5 +17,4 @@
 
 #include "mlir/Dialect/NamedTuple/IR/NamedTupleDialect.h.inc"
 
-
 #endif // MLIR_DIALECT_NAMED_TUPLE_IR_NAMED_TUPLE_DIALECT_H