FP8 enablement - add a pseudorandom number generator, add conversion methods

include/ck/tensor_operation/gpu/element/unary_element_wise_operation.hpp

@@ -6,6 +6,7 @@
 #include "ck/utility/data_type.hpp"
 #include "ck/utility/math.hpp"
 #include "ck/utility/math_v2.hpp"
+#include "ck/utility/type_convert.hpp"
 
 namespace ck {
 namespace tensor_operation {
@@ -81,6 +82,36 @@ struct PassThrough
         y = x;
     }
 #endif
+
+    template <>
+    __host__ __device__ void operator()<f8_t, f8_t>(f8_t& y, const f8_t& x) const
+    {
+        y = x;
+    }
+
+    template <>
+    __host__ __device__ void operator()<float, f8_t>(float& y, const f8_t& x) const
+    {
+        y = type_convert<float>(x);
+    }
+
+    template <>
+    __host__ __device__ void operator()<f8_t, float>(f8_t& y, const float& x) const
+    {
+        y = type_convert<f8_t>(x);
+    }
+
+    template <>
+    __host__ __device__ void operator()<half_t, f8_t>(half_t& y, const f8_t& x) const
+    {
+        y = type_convert<half_t>(x);
+    }
+
+    template <>
+    __host__ __device__ void operator()<f8_t, half_t>(f8_t& y, const half_t& x) const
+    {
+        y = type_convert<f8_t>(x);
+    }
 };
 
 struct UnaryConvert
@@ -109,6 +140,23 @@ struct ConvertBF16RTN
     }
 };
 
+struct ConvertF8SR
+{
+    // convert to fp8 using stochastic rounding (SR)
+    template <typename Y, typename X>
+    __host__ __device__ void operator()(Y& y, const X& x) const
+    {
+        // check Y datatype
+        static_assert(is_same<Y, f8_t>::value, "Data type is not supported by this operation!");
+
+        // check X datatype
+        static_assert(is_same<X, float>::value || is_same<X, half_t>::value,
+                      "Data type is not supported by this operation!");
+
+        y = f8_convert_sr<Y>(x);
+    }
+};
+
 struct Scale
 {
     __host__ __device__ Scale(float scale) : scale_(scale) {}

include/ck/utility/common_header.hpp

@@ -24,6 +24,7 @@
 #include "ck/utility/tuple.hpp"
 #include "ck/utility/tuple_helper.hpp"
 #include "ck/utility/type.hpp"
+#include "ck/utility/type_convert.hpp"
 #include "ck/utility/magic_division.hpp"
 #include "ck/utility/c_style_pointer_cast.hpp"
 #include "ck/utility/is_known_at_compile_time.hpp"

include/ck/utility/data_type.hpp

@@ -12,6 +12,7 @@ using half_t  = _Float16;
 #ifdef CK_EXPERIMENTAL_BIT_INT_EXTENSION_INT4
 using int4_t = _BitInt(4);
 #endif
+using f8_t = uint8_t;
 
 // vector_type
 template <typename T, index_t N>
@@ -142,6 +143,13 @@ struct scalar_type<int4_t>
 };
 #endif
 
+template <>
+struct scalar_type<f8_t>
+{
+    using type                           = f8_t;
+    static constexpr index_t vector_size = 1;
+};
+
 //
 template <typename T>
 struct vector_type<T, 1>
@@ -944,151 +952,13 @@ using int8x16_t = typename vector_type<int8_t, 16>::type;
 using int8x32_t = typename vector_type<int8_t, 32>::type;
 using int8x64_t = typename vector_type<int8_t, 64>::type;
 
-// Convert X to Y
-template <typename Y, typename X>
-__host__ __device__ constexpr Y type_convert(X x)
-{
-    static_assert(!std::is_reference_v<Y> && !std::is_reference_v<X>);
-
-    return static_cast<Y>(x);
-}
-
-// convert bfp16 to fp32
-template <>
-inline __host__ __device__ constexpr float type_convert<float, bhalf_t>(bhalf_t x)
-{
-    union
-    {
-        uint32_t int32;
-        float fp32;
-    } u = {uint32_t(x) << 16};
-
-    return u.fp32;
-}
-
-// convert fp32 to bfp16
-template <>
-inline __host__ __device__ constexpr bhalf_t type_convert<bhalf_t, float>(float x)
-{
-    union
-    {
-        float fp32;
-        uint32_t int32;
-    } u = {x};
-
-    return uint16_t(u.int32 >> 16);
-}
-
-// convert bfp16 to fp16 via fp32
-template <>
-inline __host__ __device__ constexpr half_t type_convert<half_t, bhalf_t>(bhalf_t x)
-{
-    float x_fp32 = type_convert<float>(x);
-
-    return static_cast<half_t>(x_fp32);
-}
-
-// convert fp16 to bfp16 via fp32
-template <>
-inline __host__ __device__ constexpr bhalf_t type_convert<bhalf_t, half_t>(half_t x)
-{
-    float x_fp32 = static_cast<float>(x);
-
-    return type_convert<bhalf_t>(x_fp32);
-}
-
-// convert bfp16 to int32 via fp32
-template <>
-inline __host__ __device__ constexpr int32_t type_convert<int32_t, bhalf_t>(bhalf_t x)
-{
-    float x_fp32 = type_convert<float>(x);
-
-    return static_cast<int32_t>(x_fp32);
-}
-
-// convert int32 to bfp16 via fp32
-template <>
-inline __host__ __device__ constexpr bhalf_t type_convert<bhalf_t, int32_t>(int32_t x)
-{
-    float x_fp32 = static_cast<float>(x);
-
-    return type_convert<bhalf_t>(x_fp32);
-}
-
-// convert bfp16 to int8 via fp32
-template <>
-inline __host__ __device__ constexpr int8_t type_convert<int8_t, bhalf_t>(bhalf_t x)
-{
-    float x_fp32 = type_convert<float>(x);
-
-    return static_cast<int8_t>(x_fp32);
-}
-
-// convert int8 to bfp16 via fp32
-template <>
-inline __host__ __device__ constexpr bhalf_t type_convert<bhalf_t, int8_t>(int8_t x)
-{
-    float x_fp32 = static_cast<float>(x);
-
-    return type_convert<bhalf_t>(x_fp32);
-}
-
-// Declare a template function for bf16 conversion using RTN
-template <typename Y, typename X>
-__host__ __device__ constexpr Y bf16_convert_rtn(X x);
-
-// Convert fp32 to bf16 with RTN if higher precision is needed
-template <>
-inline __host__ __device__ constexpr bhalf_t bf16_convert_rtn<bhalf_t, float>(float x)
-{
-    union
-    {
-        float fp32;
-        uint32_t int32;
-    } u = {x};
-
-    // When the exponent bits are not all 1s, then the value is zero, normal,
-    // or subnormal. We round the bfloat16 mantissa up by adding 0x7FFF, plus
-    // 1 if the least significant bit of the bfloat16 mantissa is 1 (odd).
-    // This causes the bfloat16's mantissa to be incremented by 1 if the 16
-    // least significant bits of the float mantissa are greater than 0x8000,
-    // or if they are equal to 0x8000 and the least significant bit of the
-    // bfloat16 mantissa is 1 (odd). This causes it to be rounded to even when
-    // the lower 16 bits are exactly 0x8000. If the bfloat16 mantissa already
-    // has the value 0x7f, then incrementing it causes it to become 0x00 and
-    // the exponent is incremented by one, which is the next higher FP value
-    // to the unrounded bfloat16 value. When the bfloat16 value is subnormal
-    // with an exponent of 0x00 and a mantissa of 0x7f, it may be rounded up
-    // to a normal value with an exponent of 0x01 and a mantissa of 0x00.
-    // When the bfloat16 value has an exponent of 0xFE and a mantissa of 0x7F,
-    // incrementing it causes it to become an exponent of 0xFF and a mantissa
-    // of 0x00, which is Inf, the next higher value to the unrounded value.
-    bool flag0 = ~u.int32 & 0x7f800000;
-
-    // When all of the exponent bits are 1, the value is Inf or NaN.
-    // Inf is indicated by a zero mantissa. NaN is indicated by any nonzero
-    // mantissa bit. Quiet NaN is indicated by the most significant mantissa
-    // bit being 1. Signaling NaN is indicated by the most significant
-    // mantissa bit being 0 but some other bit(s) being 1. If any of the
-    // lower 16 bits of the mantissa are 1, we set the least significant bit
-    // of the bfloat16 mantissa, in order to preserve signaling NaN in case
-    // the bfloat16's mantissa bits are all 0.
-    bool flag1 = !flag0 && (u.int32 & 0xffff);
-
-    u.int32 += flag0 ? 0x7fff + ((u.int32 >> 16) & 1) : 0; // Round to nearest, round to even
-    u.int32 |= flag1 ? 0x10000 : 0x0;                      // Preserve signaling NaN
-
-    return uint16_t(u.int32 >> 16);
-}
-
-// convert fp16 to bfp16 via fp32 with RTN if higher precision is needed
-template <>
-inline __host__ __device__ constexpr bhalf_t bf16_convert_rtn<bhalf_t, half_t>(half_t x)
-{
-    float x_fp32 = static_cast<float>(x);
-
-    return bf16_convert_rtn<bhalf_t>(x_fp32);
-}
+// f8
+using f8x2_t  = typename vector_type<f8_t, 2>::type;
+using f8x4_t  = typename vector_type<f8_t, 4>::type;
+using f8x8_t  = typename vector_type<f8_t, 8>::type;
+using f8x16_t = typename vector_type<f8_t, 16>::type;
+using f8x32_t = typename vector_type<f8_t, 32>::type;
+using f8x64_t = typename vector_type<f8_t, 64>::type;
 
 template <typename T>
 struct NumericLimits
@@ -1136,4 +1006,21 @@ struct NumericLimits<int4_t>
 };
 #endif // CK_EXPERIMENTAL_BIT_INT_EXTENSION_INT4
 
+template <>
+struct NumericLimits<f8_t>
+{
+    static constexpr uint8_t binary_min    = 0x08; // 0b00001000
+    static constexpr uint8_t binary_max    = 0x77; // 0b01110111
+    static constexpr uint8_t binary_lowest = 0xF7; // 0b11110111
+    static constexpr uint8_t binary_qnan   = 0x80; // 0b10000000
+
+    __host__ __device__ static constexpr f8_t Min() { return bit_cast<f8_t>(binary_min); }
+
+    __host__ __device__ static constexpr f8_t Max() { return bit_cast<f8_t>(binary_max); }
+
+    __host__ __device__ static constexpr f8_t Lowest() { return bit_cast<f8_t>(binary_lowest); }
+
+    __host__ __device__ static constexpr f8_t QuietNaN() { return bit_cast<f8_t>(binary_qnan); }
+};
+
 } // namespace ck