Move testing to unittests

Signed-off-by: Larsen, Steffen <[email protected]>

Author: steffenlarsen

sycl/test-e2e/BFloat16/bfloat16_limits.cpp

@@ -79,3 +79,71 @@ TEST(BFloat16, BF16ToFloat) {
   ASSERT_EQ(Res,
             bitsToFloatConv(std::string("11111111011111110000000000000000")));
 }
+
+TEST(BFloat16, BF16Limits) {
+  namespace sycl_ext = sycl::ext::oneapi;
+  using Limit = std::numeric_limits<sycl_ext::bfloat16>;
+  constexpr float Log10_2 = 0.30103f;
+  auto constexpr_ceil = [](float Val) constexpr -> int {
+    return Val + (float(int(Val)) == Val ? 0.f : 1.f);
+  };
+
+  static_assert(Limit::is_specialized);
+  static_assert(Limit::is_signed);
+  static_assert(!Limit::is_integer);
+  static_assert(!Limit::is_exact);
+  static_assert(Limit::has_infinity);
+  static_assert(Limit::has_quiet_NaN);
+  static_assert(Limit::has_signaling_NaN);
+  static_assert(Limit::has_denorm == std::float_denorm_style::denorm_present);
+  static_assert(!Limit::has_denorm_loss);
+  static_assert(!Limit::tinyness_before);
+  static_assert(!Limit::traps);
+  static_assert(Limit::max_exponent10 == 35);
+  static_assert(Limit::max_exponent == 127);
+  static_assert(Limit::min_exponent10 == -37);
+  static_assert(Limit::min_exponent == -126);
+  static_assert(Limit::radix == 2);
+  static_assert(Limit::digits == 8);
+  static_assert(Limit::max_digits10 ==
+                constexpr_ceil(float(Limit::digits) * Log10_2 + 1.0f));
+  static_assert(Limit::is_bounded);
+  static_assert(Limit::digits10 == int(Limit::digits * Log10_2));
+  static_assert(!Limit::is_modulo);
+  static_assert(Limit::is_iec559);
+  static_assert(Limit::round_style == std::float_round_style::round_to_nearest);
+
+  EXPECT_TRUE(sycl_ext::experimental::isnan(Limit::quiet_NaN()));
+  EXPECT_TRUE(sycl_ext::experimental::isnan(Limit::signaling_NaN()));
+  // isinf does not exist for bfloat16 currently.
+  EXPECT_EQ(Limit::infinity(),
+            sycl::bit_cast<sycl_ext::bfloat16>(uint16_t(0xff << 7)));
+  EXPECT_EQ(Limit::round_error(), sycl_ext::bfloat16(0.5f));
+  EXPECT_GT(sycl_ext::bfloat16{1.0f} + Limit::epsilon(),
+            sycl_ext::bfloat16{1.0f});
+
+  for (uint16_t Sign : {0, 1})
+    for (uint16_t Exponent = 0; Exponent < 0xff; ++Exponent)
+      for (uint16_t Significand = 0; Significand < 0x7f; ++Significand) {
+        const auto Value = sycl::bit_cast<sycl_ext::bfloat16>(
+            uint16_t((Sign << 15) | (Exponent << 7) | Significand));
+
+        EXPECT_LE(Limit::lowest(), Value);
+        EXPECT_GE(Limit::max(), Value);
+
+        // min() is the lowest normal number, so if Value is negative, 0 or a
+        // subnormal - the latter two being represented by a 0-exponent - min()
+        // must be strictly greater.
+        if (Sign || Exponent == 0x0)
+          EXPECT_GT(Limit::min(), Value);
+        else
+          EXPECT_LE(Limit::min(), Value);
+
+        // denorm_min() is the lowest subnormal number, so if Value is negative
+        // or 0 denorm_min() must be strictly greater.
+        if (Sign || (Exponent == 0x0 && Significand == 0x0))
+          EXPECT_GT(Limit::denorm_min(), Value);
+        else
+          EXPECT_LE(Limit::denorm_min(), Value);
+      }
+}