pcm/Traits: add MIN and MAX

src/pcm/PcmUtils.hxx

@@ -51,19 +51,16 @@ static inline typename Traits::value_type
 PcmClamp(typename Traits::long_type x)
 {
 	typedef typename Traits::value_type T;
-	typedef typename Traits::long_type U;
-	constexpr U MIN_VALUE = -(U(1) << (Traits::BITS - 1));
-	constexpr U MAX_VALUE = (U(1) << (Traits::BITS - 1)) - 1;
 
 	typedef std::numeric_limits<T> limits;
-	static_assert(MIN_VALUE >= limits::min(), "out of range");
-	static_assert(MAX_VALUE <= limits::max(), "out of range");
+	static_assert(Traits::MIN >= limits::min(), "out of range");
+	static_assert(Traits::MAX <= limits::max(), "out of range");
 
-	if (gcc_unlikely(x < MIN_VALUE))
-		return T(MIN_VALUE);
+	if (gcc_unlikely(x < Traits::MIN))
+		return T(Traits::MIN);
 
-	if (gcc_unlikely(x > MAX_VALUE))
-		return T(MAX_VALUE);
+	if (gcc_unlikely(x > Traits::MAX))
+		return T(Traits::MAX);
 
 	return T(x);
 }

src/pcm/Traits.hxx

@@ -74,6 +74,16 @@ struct SampleTraits<SampleFormat::S8> {
 	 * not exist if this is not an integer sample format.
 	 */
 	static constexpr unsigned BITS = sizeof(value_type) * 8;
+
+	/**
+	 * The minimum sample value.
+	 */
+	static constexpr value_type MIN = -(sum_type(1) << (BITS - 1));
+
+	/**
+	 * The maximum sample value.
+	 */
+	static constexpr value_type MAX = (sum_type(1) << (BITS - 1)) - 1;
 };
 
 template<>
@@ -87,6 +97,9 @@ struct SampleTraits<SampleFormat::S16> {
 
 	static constexpr size_t SAMPLE_SIZE = sizeof(value_type);
 	static constexpr unsigned BITS = sizeof(value_type) * 8;
+
+	static constexpr value_type MIN = -(sum_type(1) << (BITS - 1));
+	static constexpr value_type MAX = (sum_type(1) << (BITS - 1)) - 1;
 };
 
 template<>
@@ -100,6 +113,9 @@ struct SampleTraits<SampleFormat::S32> {
 
 	static constexpr size_t SAMPLE_SIZE = sizeof(value_type);
 	static constexpr unsigned BITS = sizeof(value_type) * 8;
+
+	static constexpr value_type MIN = -(sum_type(1) << (BITS - 1));
+	static constexpr value_type MAX = (sum_type(1) << (BITS - 1)) - 1;
 };
 
 template<>
@@ -113,6 +129,9 @@ struct SampleTraits<SampleFormat::S24_P32> {
 
 	static constexpr size_t SAMPLE_SIZE = sizeof(value_type);
 	static constexpr unsigned BITS = 24;
+
+	static constexpr value_type MIN = -(sum_type(1) << (BITS - 1));
+	static constexpr value_type MAX = (sum_type(1) << (BITS - 1)) - 1;
 };
 
 template<>
@@ -125,6 +144,9 @@ struct SampleTraits<SampleFormat::FLOAT> {
 	typedef float long_type;
 
 	static constexpr size_t SAMPLE_SIZE = sizeof(value_type);
+
+	static constexpr value_type MIN = -1;
+	static constexpr value_type MAX = 1;
 };
 
 #endif