[IR]Polish BFloat16Type code and Add related UT (#54440)

paddle/ir/core/builtin_type.h

@@ -35,16 +35,8 @@ namespace ir {
 /// \endcode
 ///
 
-// NOTE(dev): Currently BF16 and Int8 are not considered as a cached member
-// in IrContextImpl because they are not widely used.
-class BFloat16Type : public Type {
- public:
-  using Type::Type;
-
-  DECLARE_TYPE_UTILITY_FUNCTOR(BFloat16Type, TypeStorage);
-
-  static BFloat16Type get(IrContext *context);
-};
+// NOTE(dev): Currently Int8 are not considered as a cached member
+// in IrContextImpl because it is not widely used.
 
 class Int8Type : public Type {
  public:
@@ -79,6 +71,7 @@ class VectorType : public Type {
   };
 
 #define FOREACH_BUILTIN_TYPE(__macro) \
+  __macro(BFloat16);                  \
   __macro(Float16);                   \
   __macro(Float32);                   \
   __macro(Float64);                   \

test/cpp/ir/core/type_test.cc

@@ -77,6 +77,14 @@ TEST(type_test, built_in_type) {
   ir::IrContext *ctx = ir::IrContext::Instance();
 
   // Test 1: Test the parameterless built-in type of IrContext.
+  ir::Type bfp16_1 = ir::BFloat16Type::get(ctx);
+  ir::Type bfp16_2 = ir::BFloat16Type::get(ctx);
+  EXPECT_EQ(bfp16_1, bfp16_2);
+  EXPECT_EQ(bfp16_1.type_id(), bfp16_2.type_id());
+  EXPECT_EQ(&bfp16_1.abstract_type(),
+            &ir::AbstractType::lookup(bfp16_1.type_id(), ctx));
+  EXPECT_EQ(ir::BFloat16Type::classof(bfp16_1), 1);
+
   ir::Type fp16_1 = ir::Float16Type::get(ctx);
   ir::Type fp16_2 = ir::Float16Type::get(ctx);
   EXPECT_EQ(fp16_1, fp16_2);