triehash - Generate a perfect hash function derived from a trie.

       Julian Andres Klode <jak@jak-linux.org>

triehash v0.3                                      2020-03-08                                        TRIEHASH(1)

       triehash takes a list of words in input file and generates a function and an enumeration to describe the
       word

       The file consists of multiple lines of the form:

           [label ~ ] word [= value]

       This maps word to value, and generates an enumeration with entries of the form:

           label = value

       If label is undefined, the word will be used, the minus character will be replaced by an underscore. If
       value is undefined it is counted upwards from the last value.

       There may also be one line of the format

           [ label ~] = value

       Which defines the value to be used for non-existing keys. Note that this also changes default value for
       other keys, as for normal entries. So if you place

           = 0

       at the beginning of the file, unknown strings map to 0, and the other strings map to values starting with
       1. If label is not specified, the default is Unknown.

       triehash is available under the MIT/Expat license, see the source code for more information.

       triehash - Generate a perfect hash function derived from a trie.

-C.cfile--code=.cfile
           Generate code in the given file.

       -Hheaderfile--header=headerfile
           Generate  a  header  in  the  given  file,  containing  a  declaration  of  the  hash function and an
           enumeration.

       --enum-name=word
           The name of the enumeration.

       --function-name=word
           The name of the function.

       --label-prefix=word
           The prefix to use for labels.

       --label-uppercase
           Uppercase label names when normalizing them.

       --namespace=name
           Put the function and enum into a namespace (C++)

       --class=name
           Put the function and enum into a class (C++)

       --enum-class
           Generate an enum class instead of an enum (C++)

       --counter-name=name
           Use name for a counter that is set to the latest entry in the enumeration + 1. This can be useful for
           defining array sizes.

       --ignore-case
           Ignore case for words.

       --multi-byte=value
           Generate code reading multiple bytes at once. The value is a string of power of twos to  enable.  The
           default  value  is  320  meaning  that  8, 4, and single byte reads are enabled. Specify 0 to disable
           multi-byte completely, or add 2 if you also want to allow 2-byte reads. 2-byte reads are disabled  by
           default because they negatively affect performance on older Intel architectures.

           This generates code for both multiple bytes and single byte reads, but only enables the multiple byte
           reads of GNU C compatible compilers, as the following extensions are used:

           Byte-aligned integers
                   We must be able to generate integers that are aligned to a single byte using:

                       typedef uint64_t __attribute__((aligned (1))) triehash_uu64;

           Byte-order
                   The macros __BYTE_ORDER__ and __ORDER_LITTLE_ENDIAN__ must be defined.

           We  forcefully  disable  multi-byte  reads  on platforms where the variable __ARM_ARCH is defined and
           __ARM_FEATURE_UNALIGNED is not defined,  as  there  is  a  measurable  overhead  from  emulating  the
           unaligned reads on ARM.

       --language=language
           Generate  a file in the specified language. Currently known are 'C' and 'tree', the latter generating
           a tree.

       --include=header
           Add the header to the include statements of the header file. The value must be surrounded  by  quotes
           or angle brackets for C code. May be specified multiple times.

triehash [option] [inputfile]