[ViewVC] Diff of: cvs/cvsroot/libecb/ecb.pod

Comparing cvsroot/libecb/ecb.pod (file contents):
Revision 1.62 by root, Wed Feb 18 20:29:27 2015 UTC vs.
Revision 1.83 by root, Mon Jan 20 21:08:19 2020 UTC

…		…
58		58
59	=head2 TYPES / TYPE SUPPORT	59	=head2 TYPES / TYPE SUPPORT
60		60
61	ecb.h makes sure that the following types are defined (in the expected way):	61	ecb.h makes sure that the following types are defined (in the expected way):
62		62
63	int8_t uint8_t int16_t uint16_t	63	int8_t uint8_
64	int32_t uint32_t int64_t uint64_t	64	int16_t uint16_t
		65	int32_t uint32_
		66	int64_t uint64_t
		67	int_fast8_t uint_fast8_t
		68	int_fast16_t uint_fast16_t
		69	int_fast32_t uint_fast32_t
		70	int_fast64_t uint_fast64_t
65	intptr_t uintptr_t	71	intptr_t uintptr_t
66		72
67	The macro C<ECB_PTRSIZE> is defined to the size of a pointer on this	73	The macro C<ECB_PTRSIZE> is defined to the size of a pointer on this
68	platform (currently C<4> or C<8>) and can be used in preprocessor	74	platform (currently C<4> or C<8>) and can be used in preprocessor
69	expressions.	75	expressions.
70		76
71	For C<ptrdiff_t> and C<size_t> use C<stddef.h>.	77	For C<ptrdiff_t> and C<size_t> use C<stddef.h>/C<cstddef>.
72		78
73	=head2 LANGUAGE/ENVIRONMENT/COMPILER VERSIONS	79	=head2 LANGUAGE/ENVIRONMENT/COMPILER VERSIONS
74		80
75	All the following symbols expand to an expression that can be tested in	81	All the following symbols expand to an expression that can be tested in
76	preprocessor instructions as well as treated as a boolean (use C<!!> to	82	preprocessor instructions as well as treated as a boolean (use C<!!> to
…		…
79	=over 4	85	=over 4
80		86
81	=item ECB_C	87	=item ECB_C
82		88
83	True if the implementation defines the C<__STDC__> macro to a true value,	89	True if the implementation defines the C<__STDC__> macro to a true value,
84	while not claiming to be C++.	90	while not claiming to be C++, i..e C, but not C++.
85		91
86	=item ECB_C99	92	=item ECB_C99
87		93
88	True if the implementation claims to be compliant to C99 (ISO/IEC	94	True if the implementation claims to be compliant to C99 (ISO/IEC
89	9899:1999) or any later version, while not claiming to be C++.	95	9899:1999) or any later version, while not claiming to be C++.
90		96
91	Note that later versions (ECB_C11) remove core features again (for	97	Note that later versions (ECB_C11) remove core features again (for
92	example, variable length arrays).	98	example, variable length arrays).
93		99
94	=item ECB_C11	100	=item ECB_C11, ECB_C17
95		101
96	True if the implementation claims to be compliant to C11 (ISO/IEC	102	True if the implementation claims to be compliant to C11/C17 (ISO/IEC
97	9899:2011) or any later version, while not claiming to be C++.	103	9899:2011, :20187) or any later version, while not claiming to be C++.
98		104
99	=item ECB_CPP	105	=item ECB_CPP
100		106
101	True if the implementation defines the C<__cplusplus__> macro to a true	107	True if the implementation defines the C<__cplusplus__> macro to a true
102	value, which is typically true for C++ compilers.	108	value, which is typically true for C++ compilers.
103		109
104	=item ECB_CPP11	110	=item ECB_CPP11, ECB_CPP14, ECB_CPP17
105		111
106	True if the implementation claims to be compliant to ISO/IEC 14882:2011	112	True if the implementation claims to be compliant to C++11/C++14/C++17
107	(C++11) or any later version.	113	(ISO/IEC 14882:2011, :2014, :2017) or any later version.
		114
		115	Note that many C++20 features will likely have their own feature test
		116	macros (see e.g. L<http://eel.is/c++draft/cpp.predefined#1.8>).
		117
		118	=item ECB_OPTIMIZE_SIZE
		119
		120	Is C<1> when the compiler optimizes for size, C<0> otherwise. This symbol
		121	can also be defined before including F<ecb.h>, in which case it will be
		122	unchanged.
108		123
109	=item ECB_GCC_VERSION (major, minor)	124	=item ECB_GCC_VERSION (major, minor)
110		125
111	Expands to a true value (suitable for testing in by the preprocessor)	126	Expands to a true value (suitable for testing in by the preprocessor)
112	if the compiler used is GNU C and the version is the given version, or	127	if the compiler used is GNU C and the version is the given version, or
…		…
186	it. This is mainly useful to get the contents of a macro in string form,	201	it. This is mainly useful to get the contents of a macro in string form,
187	e.g.:	202	e.g.:
188		203
189	#define SQL_LIMIT 100	204	#define SQL_LIMIT 100
190	sql_exec ("select * from table limit " ECB_STRINGIFY (SQL_LIMIT));	205	sql_exec ("select * from table limit " ECB_STRINGIFY (SQL_LIMIT));
		206
		207	=item ECB_STRINGIFY_EXPR (expr)
		208
		209	Like C<ECB_STRINGIFY>, but additionally evaluates C<expr> to make sure it
		210	is a valid expression. This is useful to catch typos or cases where the
		211	macro isn't available:
		212
		213	#include <errno.h>
		214
		215	ECB_STRINGIFY (EDOM); // "33" (on my system at least)
		216	ECB_STRINGIFY_EXPR (EDOM); // "33"
		217
		218	// now imagine we had a typo:
		219
		220	ECB_STRINGIFY (EDAM); // "EDAM"
		221	ECB_STRINGIFY_EXPR (EDAM); // error: EDAM undefined
191		222
192	=back	223	=back
193		224
194	=head2 ATTRIBUTES	225	=head2 ATTRIBUTES
195		226
…		…
226	Similar to C<ecb_unused>, but marks a function, variable or type as	257	Similar to C<ecb_unused>, but marks a function, variable or type as
227	deprecated. This makes some compilers warn when the type is used.	258	deprecated. This makes some compilers warn when the type is used.
228		259
229	=item ecb_deprecated_message (message)	260	=item ecb_deprecated_message (message)
230		261
231	Same as C<ecb_deprecated>, but if possible, supply a diagnostic that is	262	Same as C<ecb_deprecated>, but if possible, the specified diagnostic is
232	used instead of a generic depreciation message when the object is being	263	used instead of a generic depreciation message when the object is being
233	used.	264	used.
234		265
235	=item ecb_inline	266	=item ecb_inline
236		267
237	Expands either to C<static inline> or to just C<static>, if inline	268	Expands either to (a compiler-specific equivalent of) C<static inline> or
238	isn't supported. It should be used to declare functions that should be	269	to just C<static>, if inline isn't supported. It should be used to declare
239	inlined, for code size or speed reasons.	270	functions that should be inlined, for code size or speed reasons.
240		271
241	Example: inline this function, it surely will reduce codesize.	272	Example: inline this function, it surely will reduce codesize.
242		273
243	ecb_inline int	274	ecb_inline int
244	negmul (int a, int b)	275	negmul (int a, int b)
…		…
246	return - (a * b);	277	return - (a * b);
247	}	278	}
248		279
249	=item ecb_noinline	280	=item ecb_noinline
250		281
251	Prevent a function from being inlined - it might be optimised away, but	282	Prevents a function from being inlined - it might be optimised away, but
252	not inlined into other functions. This is useful if you know your function	283	not inlined into other functions. This is useful if you know your function
253	is rarely called and large enough for inlining not to be helpful.	284	is rarely called and large enough for inlining not to be helpful.
254		285
255	=item ecb_noreturn	286	=item ecb_noreturn
256		287
…		…
473	real_reserve_method (size); /* presumably noinline */	504	real_reserve_method (size); /* presumably noinline */
474	}	505	}
475		506
476	=item ecb_assume (cond)	507	=item ecb_assume (cond)
477		508
478	Try to tell the compiler that some condition is true, even if it's not	509	Tries to tell the compiler that some condition is true, even if it's not
479	obvious.	510	obvious. This is not a function, but a statement: it cannot be used in
		511	another expression.
480		512
481	This can be used to teach the compiler about invariants or other	513	This can be used to teach the compiler about invariants or other
482	conditions that might improve code generation, but which are impossible to	514	conditions that might improve code generation, but which are impossible to
483	deduce form the code itself.	515	deduce form the code itself.
484		516
…		…
505		537
506	=item ecb_unreachable ()	538	=item ecb_unreachable ()
507		539
508	This function does nothing itself, except tell the compiler that it will	540	This function does nothing itself, except tell the compiler that it will
509	never be executed. Apart from suppressing a warning in some cases, this	541	never be executed. Apart from suppressing a warning in some cases, this
510	function can be used to implement C<ecb_assume> or similar functions.	542	function can be used to implement C<ecb_assume> or similar functionality.
511		543
512	=item ecb_prefetch (addr, rw, locality)	544	=item ecb_prefetch (addr, rw, locality)
513		545
514	Tells the compiler to try to prefetch memory at the given C<addr>ess	546	Tells the compiler to try to prefetch memory at the given C<addr>ess
515	for either reading (C<rw> = 0) or writing (C<rw> = 1). A C<locality> of	547	for either reading (C<rw> = 0) or writing (C<rw> = 1). A C<locality> of
…		…
517	the data will likely be accessed very often, and values in between mean	549	the data will likely be accessed very often, and values in between mean
518	something... in between. The memory pointed to by the address does not	550	something... in between. The memory pointed to by the address does not
519	need to be accessible (it could be a null pointer for example), but C<rw>	551	need to be accessible (it could be a null pointer for example), but C<rw>
520	and C<locality> must be compile-time constants.	552	and C<locality> must be compile-time constants.
521		553
		554	This is a statement, not a function: you cannot use it as part of an
		555	expression.
		556
522	An obvious way to use this is to prefetch some data far away, in a big	557	An obvious way to use this is to prefetch some data far away, in a big
523	array you loop over. This prefetches memory some 128 array elements later,	558	array you loop over. This prefetches memory some 128 array elements later,
524	in the hope that it will be ready when the CPU arrives at that location.	559	in the hope that it will be ready when the CPU arrives at that location.
525		560
526	int sum = 0;	561	int sum = 0;
…		…
563		598
564	=item int ecb_ctz32 (uint32_t x)	599	=item int ecb_ctz32 (uint32_t x)
565		600
566	=item int ecb_ctz64 (uint64_t x)	601	=item int ecb_ctz64 (uint64_t x)
567		602
		603	=item int ecb_ctz (T x) [C++]
		604
568	Returns the index of the least significant bit set in C<x> (or	605	Returns the index of the least significant bit set in C<x> (or
569	equivalently the number of bits set to 0 before the least significant bit	606	equivalently the number of bits set to 0 before the least significant bit
570	set), starting from 0. If C<x> is 0 the result is undefined.	607	set), starting from 0. If C<x> is 0 the result is undefined.
571		608
572	For smaller types than C<uint32_t> you can safely use C<ecb_ctz32>.	609	For smaller types than C<uint32_t> you can safely use C<ecb_ctz32>.
573		610
		611	The overloaded C++ C<ecb_ctz> function supports C<uint8_t>, C<uint16_t>,
		612	C<uint32_t> and C<uint64_t> types.
		613
574	For example:	614	For example:
575		615
576	ecb_ctz32 (3) = 0	616	ecb_ctz32 (3) = 0
577	ecb_ctz32 (6) = 1	617	ecb_ctz32 (6) = 1
578		618
579	=item bool ecb_is_pot32 (uint32_t x)	619	=item bool ecb_is_pot32 (uint32_t x)
580		620
581	=item bool ecb_is_pot64 (uint32_t x)	621	=item bool ecb_is_pot64 (uint32_t x)
582		622
		623	=item bool ecb_is_pot (T x) [C++]
		624
583	Return true iff C<x> is a power of two or C<x == 0>.	625	Returns true iff C<x> is a power of two or C<x == 0>.
584		626
585	For smaller types then C<uint32_t> you can safely use C<ecb_is_pot32>.	627	For smaller types than C<uint32_t> you can safely use C<ecb_is_pot32>.
		628
		629	The overloaded C++ C<ecb_is_pot> function supports C<uint8_t>, C<uint16_t>,
		630	C<uint32_t> and C<uint64_t> types.
586		631
587	=item int ecb_ld32 (uint32_t x)	632	=item int ecb_ld32 (uint32_t x)
588		633
589	=item int ecb_ld64 (uint64_t x)	634	=item int ecb_ld64 (uint64_t x)
		635
		636	=item int ecb_ld64 (T x) [C++]
590		637
591	Returns the index of the most significant bit set in C<x>, or the number	638	Returns the index of the most significant bit set in C<x>, or the number
592	of digits the number requires in binary (so that C<< 2**ld <= x <	639	of digits the number requires in binary (so that C<< 2**ld <= x <
593	2**(ld+1) >>). If C<x> is 0 the result is undefined. A common use case is	640	2**(ld+1) >>). If C<x> is 0 the result is undefined. A common use case is
594	to compute the integer binary logarithm, i.e. C<floor (log2 (n))>, for	641	to compute the integer binary logarithm, i.e. C<floor (log2 (n))>, for
…		…
599	the given data type), while C<ecb_ld> returns how many bits the number	646	the given data type), while C<ecb_ld> returns how many bits the number
600	itself requires.	647	itself requires.
601		648
602	For smaller types than C<uint32_t> you can safely use C<ecb_ld32>.	649	For smaller types than C<uint32_t> you can safely use C<ecb_ld32>.
603		650
		651	The overloaded C++ C<ecb_ld> function supports C<uint8_t>, C<uint16_t>,
		652	C<uint32_t> and C<uint64_t> types.
		653
604	=item int ecb_popcount32 (uint32_t x)	654	=item int ecb_popcount32 (uint32_t x)
605		655
606	=item int ecb_popcount64 (uint64_t x)	656	=item int ecb_popcount64 (uint64_t x)
607		657
		658	=item int ecb_popcount (T x) [C++]
		659
608	Returns the number of bits set to 1 in C<x>.	660	Returns the number of bits set to 1 in C<x>.
609		661
610	For smaller types than C<uint32_t> you can safely use C<ecb_popcount32>.	662	For smaller types than C<uint32_t> you can safely use C<ecb_popcount32>.
		663
		664	The overloaded C++ C<ecb_popcount> function supports C<uint8_t>, C<uint16_t>,
		665	C<uint32_t> and C<uint64_t> types.
611		666
612	For example:	667	For example:
613		668
614	ecb_popcount32 (7) = 3	669	ecb_popcount32 (7) = 3
615	ecb_popcount32 (255) = 8	670	ecb_popcount32 (255) = 8
…		…
618		673
619	=item uint16_t ecb_bitrev16 (uint16_t x)	674	=item uint16_t ecb_bitrev16 (uint16_t x)
620		675
621	=item uint32_t ecb_bitrev32 (uint32_t x)	676	=item uint32_t ecb_bitrev32 (uint32_t x)
622		677
		678	=item T ecb_bitrev (T x) [C++]
		679
623	Reverses the bits in x, i.e. the MSB becomes the LSB, MSB-1 becomes LSB+1	680	Reverses the bits in x, i.e. the MSB becomes the LSB, MSB-1 becomes LSB+1
624	and so on.	681	and so on.
625		682
		683	The overloaded C++ C<ecb_bitrev> function supports C<uint8_t>, C<uint16_t> and C<uint32_t> types.
		684
626	Example:	685	Example:
627		686
628	ecb_bitrev8 (0xa7) = 0xea	687	ecb_bitrev8 (0xa7) = 0xea
629	ecb_bitrev32 (0xffcc4411) = 0x882233ff	688	ecb_bitrev32 (0xffcc4411) = 0x882233ff
630		689
		690	=item T ecb_bitrev (T x) [C++]
		691
		692	Overloaded C++ bitrev function.
		693
		694	C<T> must be one of C<uint8_t>, C<uint16_t> or C<uint32_t>.
		695
631	=item uint32_t ecb_bswap16 (uint32_t x)	696	=item uint32_t ecb_bswap16 (uint32_t x)
632		697
633	=item uint32_t ecb_bswap32 (uint32_t x)	698	=item uint32_t ecb_bswap32 (uint32_t x)
634		699
635	=item uint64_t ecb_bswap64 (uint64_t x)	700	=item uint64_t ecb_bswap64 (uint64_t x)
		701
		702	=item T ecb_bswap (T x)
636		703
637	These functions return the value of the 16-bit (32-bit, 64-bit) value	704	These functions return the value of the 16-bit (32-bit, 64-bit) value
638	C<x> after reversing the order of bytes (0x11223344 becomes 0x44332211 in	705	C<x> after reversing the order of bytes (0x11223344 becomes 0x44332211 in
639	C<ecb_bswap32>).	706	C<ecb_bswap32>).
640		707
		708	The overloaded C++ C<ecb_bswap> function supports C<uint8_t>, C<uint16_t>,
		709	C<uint32_t> and C<uint64_t> types.
		710
641	=item uint8_t ecb_rotl8 (uint8_t x, unsigned int count)	711	=item uint8_t ecb_rotl8 (uint8_t x, unsigned int count)
642		712
643	=item uint16_t ecb_rotl16 (uint16_t x, unsigned int count)	713	=item uint16_t ecb_rotl16 (uint16_t x, unsigned int count)
644		714
645	=item uint32_t ecb_rotl32 (uint32_t x, unsigned int count)	715	=item uint32_t ecb_rotl32 (uint32_t x, unsigned int count)
…		…
660		730
661	Current GCC versions understand these functions and usually compile them	731	Current GCC versions understand these functions and usually compile them
662	to "optimal" code (e.g. a single C<rol> or a combination of C<shld> on	732	to "optimal" code (e.g. a single C<rol> or a combination of C<shld> on
663	x86).	733	x86).
664		734
		735	=item T ecb_rotl (T x, unsigned int count) [C++]
		736
		737	=item T ecb_rotr (T x, unsigned int count) [C++]
		738
		739	Overloaded C++ rotl/rotr functions.
		740
		741	C<T> must be one of C<uint8_t>, C<uint16_t>, C<uint32_t> or C<uint64_t>.
		742
665	=back	743	=back
666		744
		745	=head2 HOST ENDIANNESS CONVERSION
		746
		747	=over 4
		748
		749	=item uint_fast16_t ecb_be_u16_to_host (uint_fast16_t v)
		750
		751	=item uint_fast32_t ecb_be_u32_to_host (uint_fast32_t v)
		752
		753	=item uint_fast64_t ecb_be_u64_to_host (uint_fast64_t v)
		754
		755	=item uint_fast16_t ecb_le_u16_to_host (uint_fast16_t v)
		756
		757	=item uint_fast32_t ecb_le_u32_to_host (uint_fast32_t v)
		758
		759	=item uint_fast64_t ecb_le_u64_to_host (uint_fast64_t v)
		760
		761	Convert an unsigned 16, 32 or 64 bit value from big or little endian to host byte order.
		762
		763	The naming convention is C<ecb_>(C<be>\|C<le>)C<_u>C<16\|32\|64>C<_to_host>,
		764	where C<be> and C<le> stand for big endian and little endian, respectively.
		765
		766	=item uint_fast16_t ecb_host_to_be_u16 (uint_fast16_t v)
		767
		768	=item uint_fast32_t ecb_host_to_be_u32 (uint_fast32_t v)
		769
		770	=item uint_fast64_t ecb_host_to_be_u64 (uint_fast64_t v)
		771
		772	=item uint_fast16_t ecb_host_to_le_u16 (uint_fast16_t v)
		773
		774	=item uint_fast32_t ecb_host_to_le_u32 (uint_fast32_t v)
		775
		776	=item uint_fast64_t ecb_host_to_le_u64 (uint_fast64_t v)
		777
		778	Like above, but converts I<from> host byte order to the specified
		779	endianness.
		780
		781	=back
		782
		783	In C++ the following additional template functions are supported:
		784
		785	=over 4
		786
		787	=item T ecb_be_to_host (T v)
		788
		789	=item T ecb_le_to_host (T v)
		790
		791	=item T ecb_host_to_be (T v)
		792
		793	=item T ecb_host_to_le (T v)
		794
		795	These functions work like their C counterparts, above, but use templates,
		796	which make them useful in generic code.
		797
		798	C<T> must be one of C<uint8_t>, C<uint16_t>, C<uint32_t> or C<uint64_t>
		799	(so unlike their C counterparts, there is a version for C<uint8_t>, which
		800	again can be useful in generic code).
		801
		802	=head2 UNALIGNED LOAD/STORE
		803
		804	These function load or store unaligned multi-byte values.
		805
		806	=over 4
		807
		808	=item uint_fast16_t ecb_peek_u16_u (const void *ptr)
		809
		810	=item uint_fast32_t ecb_peek_u32_u (const void *ptr)
		811
		812	=item uint_fast64_t ecb_peek_u64_u (const void *ptr)
		813
		814	These functions load an unaligned, unsigned 16, 32 or 64 bit value from
		815	memory.
		816
		817	=item uint_fast16_t ecb_peek_be_u16_u (const void *ptr)
		818
		819	=item uint_fast32_t ecb_peek_be_u32_u (const void *ptr)
		820
		821	=item uint_fast64_t ecb_peek_be_u64_u (const void *ptr)
		822
		823	=item uint_fast16_t ecb_peek_le_u16_u (const void *ptr)
		824
		825	=item uint_fast32_t ecb_peek_le_u32_u (const void *ptr)
		826
		827	=item uint_fast64_t ecb_peek_le_u64_u (const void *ptr)
		828
		829	Like above, but additionally convert from big endian (C<be>) or little
		830	endian (C<le>) byte order to host byte order while doing so.
		831
		832	=item ecb_poke_u16_u (void *ptr, uint16_t v)
		833
		834	=item ecb_poke_u32_u (void *ptr, uint32_t v)
		835
		836	=item ecb_poke_u64_u (void *ptr, uint64_t v)
		837
		838	These functions store an unaligned, unsigned 16, 32 or 64 bit value to
		839	memory.
		840
		841	=item ecb_poke_be_u16_u (void *ptr, uint_fast16_t v)
		842
		843	=item ecb_poke_be_u32_u (void *ptr, uint_fast32_t v)
		844
		845	=item ecb_poke_be_u64_u (void *ptr, uint_fast64_t v)
		846
		847	=item ecb_poke_le_u16_u (void *ptr, uint_fast16_t v)
		848
		849	=item ecb_poke_le_u32_u (void *ptr, uint_fast32_t v)
		850
		851	=item ecb_poke_le_u64_u (void *ptr, uint_fast64_t v)
		852
		853	Like above, but additionally convert from host byte order to big endian
		854	(C<be>) or little endian (C<le>) byte order while doing so.
		855
		856	=back
		857
		858	In C++ the following additional template functions are supported:
		859
		860	=over 4
		861
		862	=item T ecb_peek<T> (const void *ptr)
		863
		864	=item T ecb_peek_be<T> (const void *ptr)
		865
		866	=item T ecb_peek_le<T> (const void *ptr)
		867
		868	=item T ecb_peek_u<T> (const void *ptr)
		869
		870	=item T ecb_peek_be_u<T> (const void *ptr)
		871
		872	=item T ecb_peek_le_u<T> (const void *ptr)
		873
		874	Similarly to their C counterparts, these functions load an unsigned 8, 16,
		875	32 or 64 bit value from memory, with optional conversion from big/little
		876	endian.
		877
		878	Since the type cannot be deduced, it has to be specified explicitly, e.g.
		879
		880	uint_fast16_t v = ecb_peek<uint16_t> (ptr);
		881
		882	C<T> must be one of C<uint8_t>, C<uint16_t>, C<uint32_t> or C<uint64_t>.
		883
		884	Unlike their C counterparts, these functions support 8 bit quantities
		885	(C<uint8_t>) and also have an aligned version (without the C<_u> prefix),
		886	all of which hopefully makes them more useful in generic code.
		887
		888	=item ecb_poke (void *ptr, T v)
		889
		890	=item ecb_poke_be (void *ptr, T v)
		891
		892	=item ecb_poke_le (void *ptr, T v)
		893
		894	=item ecb_poke_u (void *ptr, T v)
		895
		896	=item ecb_poke_be_u (void *ptr, T v)
		897
		898	=item ecb_poke_le_u (void *ptr, T v)
		899
		900	Again, similarly to their C counterparts, these functions store an
		901	unsigned 8, 16, 32 or z64 bit value to memory, with optional conversion to
		902	big/little endian.
		903
		904	C<T> must be one of C<uint8_t>, C<uint16_t>, C<uint32_t> or C<uint64_t>.
		905
		906	Unlike their C counterparts, these functions support 8 bit quantities
		907	(C<uint8_t>) and also have an aligned version (without the C<_u> prefix),
		908	all of which hopefully makes them more useful in generic code.
		909
		910	=back
		911
667	=head2 FLOATING POINT FIDDLING	912	=head2 FLOATING POINT FIDDLING
668		913
669	=over 4	914	=over 4
670		915
671	=item ECB_INFINITY	916	=item ECB_INFINITY [-UECB_NO_LIBM]
672		917
673	Evaluates to positive infinity if supported by the platform, otherwise to	918	Evaluates to positive infinity if supported by the platform, otherwise to
674	a truly huge number.	919	a truly huge number.
675		920
676	=item ECB_NON	921	=item ECB_NAN [-UECB_NO_LIBM]
677		922
678	Evaluates to a quiet NAN if supported by the platform, otherwise to	923	Evaluates to a quiet NAN if supported by the platform, otherwise to
679	C<ECB_INFINITY>.	924	C<ECB_INFINITY>.
680		925
681	=item float ecb_ldexpf (float x, int exp)	926	=item float ecb_ldexpf (float x, int exp) [-UECB_NO_LIBM]
682		927
683	Same as C<ldexpf>, but always available.	928	Same as C<ldexpf>, but always available.
684		929
		930	=item uint32_t ecb_float_to_binary16 (float x) [-UECB_NO_LIBM]
		931
685	=item uint32_t ecb_float_to_binary32 (float x) [-UECB_NO_LIBM]	932	=item uint32_t ecb_float_to_binary32 (float x) [-UECB_NO_LIBM]
686		933
687	=item uint64_t ecb_double_to_binary64 (double x) [-UECB_NO_LIBM]	934	=item uint64_t ecb_double_to_binary64 (double x) [-UECB_NO_LIBM]
688		935
689	These functions each take an argument in the native C<float> or C<double>	936	These functions each take an argument in the native C<float> or C<double>
690	type and return the IEEE 754 bit representation of it.	937	type and return the IEEE 754 bit representation of it (binary16/half,
		938	binary32/single or binary64/double precision).
691		939
692	The bit representation is just as IEEE 754 defines it, i.e. the sign bit	940	The bit representation is just as IEEE 754 defines it, i.e. the sign bit
693	will be the most significant bit, followed by exponent and mantissa.	941	will be the most significant bit, followed by exponent and mantissa.
694		942
695	This function should work even when the native floating point format isn't	943	This function should work even when the native floating point format isn't
…		…
699		947
700	On all modern platforms (where C<ECB_STDFP> is true), the compiler should	948	On all modern platforms (where C<ECB_STDFP> is true), the compiler should
701	be able to optimise away this function completely.	949	be able to optimise away this function completely.
702		950
703	These functions can be helpful when serialising floats to the network - you	951	These functions can be helpful when serialising floats to the network - you
704	can serialise the return value like a normal uint32_t/uint64_t.	952	can serialise the return value like a normal uint16_t/uint32_t/uint64_t.
705		953
706	Another use for these functions is to manipulate floating point values	954	Another use for these functions is to manipulate floating point values
707	directly.	955	directly.
708		956
709	Silly example: toggle the sign bit of a float.	957	Silly example: toggle the sign bit of a float.
…		…
716		964
717	=item float ecb_binary16_to_float (uint16_t x) [-UECB_NO_LIBM]	965	=item float ecb_binary16_to_float (uint16_t x) [-UECB_NO_LIBM]
718		966
719	=item float ecb_binary32_to_float (uint32_t x) [-UECB_NO_LIBM]	967	=item float ecb_binary32_to_float (uint32_t x) [-UECB_NO_LIBM]
720		968
721	=item double ecb_binary32_to_double (uint64_t x) [-UECB_NO_LIBM]	969	=item double ecb_binary64_to_double (uint64_t x) [-UECB_NO_LIBM]
722		970
723	The reverse operation of the previous function - takes the bit	971	The reverse operation of the previous function - takes the bit
724	representation of an IEEE binary16, binary32 or binary64 number and	972	representation of an IEEE binary16, binary32 or binary64 number (half,
725	converts it to the native C<float> or C<double> format.	973	single or double precision) and converts it to the native C<float> or
		974	C<double> format.
726		975
727	This function should work even when the native floating point format isn't	976	This function should work even when the native floating point format isn't
728	IEEE compliant, of course at a speed and code size penalty, and of course	977	IEEE compliant, of course at a speed and code size penalty, and of course
729	also within reasonable limits (it tries to convert normals and denormals,	978	also within reasonable limits (it tries to convert normals and denormals,
730	and might be lucky for infinities, and with extraordinary luck, also for	979	and might be lucky for infinities, and with extraordinary luck, also for
731	negative zero).	980	negative zero).
732		981
733	On all modern platforms (where C<ECB_STDFP> is true), the compiler should	982	On all modern platforms (where C<ECB_STDFP> is true), the compiler should
734	be able to optimise away this function completely.	983	be able to optimise away this function completely.
		984
		985	=item uint16_t ecb_binary32_to_binary16 (uint32_t x)
		986
		987	=item uint32_t ecb_binary16_to_binary32 (uint16_t x)
		988
		989	Convert a IEEE binary32/single precision to binary16/half format, and vice
		990	versa, handling all details (round-to-nearest-even, subnormals, infinity
		991	and NaNs) correctly.
		992
		993	These are functions are available under C<-DECB_NO_LIBM>, since
		994	they do not rely on the platform floating point format. The
		995	C<ecb_float_to_binary16> and C<ecb_binary16_to_float> functions are
		996	usually what you want.
735		997
736	=back	998	=back
737		999
738	=head2 ARITHMETIC	1000	=head2 ARITHMETIC
739		1001
…		…
820	dependencies on the math library (usually called F<-lm>) - these are	1082	dependencies on the math library (usually called F<-lm>) - these are
821	marked with [-UECB_NO_LIBM].	1083	marked with [-UECB_NO_LIBM].
822		1084
823	=back	1085	=back
824		1086
		1087	=head1 UNDOCUMENTED FUNCTIONALITY
825		1088
		1089	F<ecb.h> is full of undocumented functionality as well, some of which is
		1090	intended to be internal-use only, some of which we forgot to document, and
		1091	some of which we hide because we are not sure we will keep the interface
		1092	stable.
		1093
		1094	While you are welcome to rummage around and use whatever you find useful
		1095	(we can't stop you), keep in mind that we will change undocumented
		1096	functionality in incompatible ways without thinking twice, while we are
		1097	considerably more conservative with documented things.
		1098
		1099	=head1 AUTHORS
		1100
		1101	C<libecb> is designed and maintained by:
		1102
		1103	Emanuele Giaquinta <e.giaquinta@glauco.it>
		1104	Marc Alexander Lehmann <schmorp@schmorp.de>
		1105
		1106

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Comparing cvsroot/libecb/ecb.pod (file contents): Revision 1.62 by root, Wed Feb 18 20:29:27 2015 UTC vs. Revision 1.83 by root, Mon Jan 20 21:08:19 2020 UTC

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Comparing cvsroot/libecb/ecb.pod (file contents):
Revision 1.62 by root, Wed Feb 18 20:29:27 2015 UTC vs.
Revision 1.83 by root, Mon Jan 20 21:08:19 2020 UTC