Add predefined datatypes for FP8 formats

Adds predefined datatypes for FP8 data in E4M3 and E5M2 formats

Does not add support for any native FP8 types; datatype conversions are performed in software

Author: jhendersonHDF

c++/src/H5PredType.cpp

@@ -154,6 +154,8 @@ PredType *PredType::IEEE_F64LE_;
 
 PredType *PredType::FLOAT_BFLOAT16BE_;
 PredType *PredType::FLOAT_BFLOAT16LE_;
+PredType *PredType::FLOAT_F8E4M3_;
+PredType *PredType::FLOAT_F8E5M2_;
 
 PredType *PredType::UNIX_D32BE_;
 PredType *PredType::UNIX_D32LE_;
@@ -344,6 +346,8 @@ PredType::makePredTypes()
 
     FLOAT_BFLOAT16BE_ = new PredType(H5T_FLOAT_BFLOAT16BE);
     FLOAT_BFLOAT16LE_ = new PredType(H5T_FLOAT_BFLOAT16LE);
+    FLOAT_F8E4M3_     = new PredType(H5T_FLOAT_F8E4M3);
+    FLOAT_F8E5M2_     = new PredType(H5T_FLOAT_F8E5M2);
 
     UNIX_D32BE_ = new PredType(H5T_UNIX_D32BE);
     UNIX_D32LE_ = new PredType(H5T_UNIX_D32LE);
@@ -500,6 +504,8 @@ PredType::deleteConstants()
 
     delete FLOAT_BFLOAT16BE_;
     delete FLOAT_BFLOAT16LE_;
+    delete FLOAT_F8E4M3_;
+    delete FLOAT_F8E5M2_;
 
     delete UNIX_D32BE_;
     delete UNIX_D32LE_;
@@ -660,6 +666,8 @@ const PredType &PredType::IEEE_F64LE = *IEEE_F64LE_;
 
 const PredType &PredType::FLOAT_BFLOAT16BE = *FLOAT_BFLOAT16BE_;
 const PredType &PredType::FLOAT_BFLOAT16LE = *FLOAT_BFLOAT16LE_;
+const PredType &PredType::FLOAT_F8E4M3     = *FLOAT_F8E4M3_;
+const PredType &PredType::FLOAT_F8E5M2     = *FLOAT_F8E5M2_;
 
 const PredType &PredType::UNIX_D32BE = *UNIX_D32BE_;
 const PredType &PredType::UNIX_D32LE = *UNIX_D32LE_;

c++/src/H5PredType.h

@@ -94,6 +94,8 @@ class H5CPP_DLL PredType : public AtomType {
 
     static const PredType &FLOAT_BFLOAT16BE;
     static const PredType &FLOAT_BFLOAT16LE;
+    static const PredType &FLOAT_F8E4M3;
+    static const PredType &FLOAT_F8E5M2;
 
     static const PredType &UNIX_D32BE;
     static const PredType &UNIX_D32LE;
@@ -267,6 +269,8 @@ class H5CPP_DLL PredType : public AtomType {
 
     static PredType *FLOAT_BFLOAT16BE_;
     static PredType *FLOAT_BFLOAT16LE_;
+    static PredType *FLOAT_F8E4M3_;
+    static PredType *FLOAT_F8E5M2_;
 
     static PredType *UNIX_D32BE_;
     static PredType *UNIX_D32LE_;

doxygen/dox/DDLBNF200.dox

@@ -100,6 +100,7 @@ This section contains a brief explanation of the symbols used in the DDL.
             H5T_IEEE_F32BE       | H5T_IEEE_F32LE       |
             H5T_IEEE_F64BE       | H5T_IEEE_F64LE       |
             H5T_FLOAT_BFLOAT16BE | H5T_FLOAT_BFLOAT16LE |
+            H5T_FLOAT_F8E4M3     | H5T_FLOAT_F8E5M2     |
             H5T_NATIVE_FLOAT16   | H5T_NATIVE_FLOAT     |
             H5T_NATIVE_DOUBLE    | H5T_NATIVE_LDOUBLE
 

doxygen/examples/tables/predefinedDatatypes.dox

@@ -50,6 +50,14 @@
 <td>#H5T_FLOAT_BFLOAT16LE</td>
 <td>16-bit little-endian bfloat16 floating point</td>
 </tr>
+<tr>
+<td>#H5T_FLOAT_F8E4M3</td>
+<td>8-bit FP8 E4M3 (4 exponent bits, 3 mantissa bits) floating point</td>
+</tr>
+<tr>
+<td>#H5T_FLOAT_F8E5M2</td>
+<td>8-bit FP8 E5M2 (5 exponent bits, 2 mantissa bits) floating point</td>
+</tr>
 </table>
 //! [predefined_alt_float_datatypes_table]
  *

fortran/src/H5_f.c

@@ -253,6 +253,10 @@ h5init_types_c(hid_t_f *types, hid_t_f *floatingtypes, hid_t_f *integertypes)
         return ret_value;
     if ((floatingtypes[7] = (hid_t_f)H5Tcopy(H5T_FLOAT_BFLOAT16LE)) < 0)
         return ret_value;
+    if ((floatingtypes[8] = (hid_t_f)H5Tcopy(H5T_FLOAT_F8E4M3)) < 0)
+        return ret_value;
+    if ((floatingtypes[9] = (hid_t_f)H5Tcopy(H5T_FLOAT_F8E5M2)) < 0)
+        return ret_value;
 
     if ((integertypes[0] = (hid_t_f)H5Tcopy(H5T_STD_I8BE)) < 0)
         return ret_value;

fortran/src/H5_ff.F90

@@ -295,6 +295,8 @@ END FUNCTION h5init1_flags_c
     H5T_IEEE_F16LE       = floating_types(6)
     H5T_FLOAT_BFLOAT16BE = floating_types(7)
     H5T_FLOAT_BFLOAT16LE = floating_types(8)
+    H5T_FLOAT_F8E4M3     = floating_types(9)
+    H5T_FLOAT_F8E5M2     = floating_types(10)
 
     H5T_STD_I8BE   = integer_types(1)
     H5T_STD_I8LE   = integer_types(2)

fortran/src/H5f90global.F90

@@ -63,7 +63,7 @@ MODULE H5GLOBAL
   ! Do not forget to change these values when new predefined
   ! datatypes are added
   INTEGER, PARAMETER :: PREDEF_TYPES_LEN = 19
-  INTEGER, PARAMETER :: FLOATING_TYPES_LEN = 8
+  INTEGER, PARAMETER :: FLOATING_TYPES_LEN = 10
   INTEGER, PARAMETER :: INTEGER_TYPES_LEN = 28
 
   ! These arrays need to be global because they are used in
@@ -91,6 +91,8 @@ MODULE H5GLOBAL
   !DEC$ATTRIBUTES DLLEXPORT :: H5T_IEEE_F16LE
   !DEC$ATTRIBUTES DLLEXPORT :: H5T_FLOAT_BFLOAT16BE
   !DEC$ATTRIBUTES DLLEXPORT :: H5T_FLOAT_BFLOAT16LE
+  !DEC$ATTRIBUTES DLLEXPORT :: H5T_FLOAT_F8E4M3
+  !DEC$ATTRIBUTES DLLEXPORT :: H5T_FLOAT_F8E5M2
   !DEC$ATTRIBUTES DLLEXPORT :: H5T_STD_I8BE
   !DEC$ATTRIBUTES DLLEXPORT :: H5T_STD_I8LE
   !DEC$ATTRIBUTES DLLEXPORT :: H5T_STD_I16BE
@@ -145,6 +147,8 @@ MODULE H5GLOBAL
   INTEGER(HID_T) :: H5T_IEEE_F16LE  !< H5T_IEEE_F16LE
   INTEGER(HID_T) :: H5T_FLOAT_BFLOAT16BE  !< H5T_FLOAT_BFLOAT16BE
   INTEGER(HID_T) :: H5T_FLOAT_BFLOAT16LE  !< H5T_FLOAT_BFLOAT16LE
+  INTEGER(HID_T) :: H5T_FLOAT_F8E4M3  !< H5T_FLOAT_F8E4M3
+  INTEGER(HID_T) :: H5T_FLOAT_F8E5M2  !< H5T_FLOAT_F8E5M2
   INTEGER(HID_T) :: H5T_STD_I8BE  !< H5T_STD_I8BE
   INTEGER(HID_T) :: H5T_STD_I8LE  !< H5T_STD_I8LE
   INTEGER(HID_T) :: H5T_STD_I16BE  !< H5T_STD_I16BE

hl/src/H5LT.c

@@ -2311,6 +2311,12 @@ H5LT_dtype_to_text(hid_t dtype, char *dt_str, H5LT_lang_t lang, size_t *slen, bo
             else if (H5Tequal(dtype, H5T_FLOAT_BFLOAT16LE)) {
                 snprintf(dt_str, *slen, "H5T_FLOAT_BFLOAT16LE");
             }
+            else if (H5Tequal(dtype, H5T_FLOAT_F8E4M3)) {
+                snprintf(dt_str, *slen, "H5T_FLOAT_F8E4M3");
+            }
+            else if (H5Tequal(dtype, H5T_FLOAT_F8E5M2)) {
+                snprintf(dt_str, *slen, "H5T_FLOAT_F8E5M2");
+            }
 #ifdef H5_HAVE__FLOAT16
             else if (H5Tequal(dtype, H5T_NATIVE_FLOAT16)) {
                 snprintf(dt_str, *slen, "H5T_NATIVE_FLOAT16");