[ImportVerilog] Support assignment patterns with integer type (#7646)

Allow `'{...}` assignment patterns to be used to assign integer values.
Slang already computes the value for each element in the resulting type.
All that's needed is a concat with the right operand order.

lib/Conversion/ImportVerilog/Expressions.cpp

@@ -735,6 +735,13 @@ struct RvalueExprVisitor {
       for (unsigned elementIdx = 0; elementIdx < elementCount; ++elementIdx)
         elements.push_back(elements[elementIdx]);
 
+    // Handle integers.
+    if (auto intType = dyn_cast<moore::IntType>(type)) {
+      assert(intType.getWidth() == elements.size());
+      std::reverse(elements.begin(), elements.end());
+      return builder.create<moore::ConcatOp>(loc, intType, elements);
+    }
+
     // Handle packed structs.
     if (auto structType = dyn_cast<moore::StructType>(type)) {
       assert(structType.getMembers().size() == elements.size());

test/Conversion/ImportVerilog/basic.sv

@@ -655,6 +655,8 @@ module Expressions;
   bit [1:0][31:0] arrayInt;
   // CHECK: %uarrayInt = moore.variable : <uarray<2 x i32>>
   bit [31:0] uarrayInt [2];
+  // CHECK: %m = moore.variable : <l4>
+  logic [3:0] m;
 
   initial begin
     // CHECK: moore.constant 0 : i32
@@ -1275,6 +1277,13 @@ module Expressions;
     // CHECK: [[TMP3:%.+]] = moore.array_create [[TMP0]], [[TMP1]], [[TMP2]], [[TMP0]], [[TMP1]], [[TMP2]] : !moore.i4, !moore.i4, !moore.i4, !moore.i4, !moore.i4, !moore.i4 -> uarray<6 x i4>
     // CHECK: moore.array_create [[TMP3]], [[TMP3]], [[TMP3]] : !moore.uarray<6 x i4>, !moore.uarray<6 x i4>, !moore.uarray<6 x i4> -> uarray<3 x uarray<6 x i4>>
     arr = '{3{'{2{4'd1, 4'd2, 4'd3}}}};
+
+    // CHECK: [[TMP0:%.+]] = moore.constant 0 :
+    // CHECK: [[TMP1:%.+]] = moore.constant 0 :
+    // CHECK: [[TMP2:%.+]] = moore.constant 1 :
+    // CHECK: [[TMP3:%.+]] = moore.constant 0 :
+    // CHECK: moore.concat [[TMP3]], [[TMP2]], [[TMP1]], [[TMP0]] : (!moore.l1, !moore.l1, !moore.l1, !moore.l1) -> l4
+    m = '{default: '0, 2: '1};
 
     //===------------------------------------------------------------------===//
     // Builtin Functions