test: Add tests for f{32,64}.nearest instructions

wasmx · Aug 14, 2020 · e1b4367 · e1b4367
1 parent 0744187
commit e1b4367
Showing 1 changed file with 38 additions and 0 deletions.
diff --git a/test/unittests/execute_floating_point_test.cpp b/test/unittests/execute_floating_point_test.cpp
@@ -289,6 +289,7 @@ TYPED_TEST(execute_floating_point_types, unop_nan_propagation)
         Instr::f32_ceil,
         Instr::f32_floor,
         Instr::f32_trunc,
+        Instr::f32_nearest,
         Instr::f32_sqrt,
     };
 
@@ -533,6 +534,43 @@ TYPED_TEST(execute_floating_point_types, trunc)
     }
 }
 
+TYPED_TEST(execute_floating_point_types, nearest)
+{
+    auto instance = instantiate(parse(this->get_unop_code(Instr::f32_nearest)));
+    const auto exec = [&](auto arg) { return execute(*instance, 0, {arg}); };
+
+    for (const auto& [arg, expected_trunc] : this->positive_trunc_tests)
+    {
+        ASSERT_EQ(expected_trunc, std::trunc(expected_trunc));
+        const auto is_even = std::fmod(expected_trunc, TypeParam{2}) == TypeParam{0};
+
+        // Computing "expected" is expanded to individual cases to check code coverage.
+        TypeParam expected;
+        if (arg == expected_trunc)
+        {
+            expected = expected_trunc;
+        }
+        else
+        {
+            const auto diff = arg - expected_trunc;
+            ASSERT_LT(diff, TypeParam{1});
+            ASSERT_GT(diff, TypeParam{0});
+
+            if (diff < TypeParam{0.5})
+                expected = expected_trunc;  // NOLINT
+            else if (diff > TypeParam{0.5})
+                expected = expected_trunc + TypeParam{1};  // NOLINT
+            else if (is_even)
+                expected = expected_trunc;
+            else
+                expected = expected_trunc + TypeParam{1};
+        }
+
+        EXPECT_THAT(exec(arg), Result(expected)) << arg << ": " << expected;
+        EXPECT_THAT(exec(-arg), Result(-expected)) << -arg << ": " << -expected;
+    }
+}
+
 
 TYPED_TEST(execute_floating_point_types, sqrt)
 {