1 #ifndef COMPILER_H
2 #define COMPILER_H
3 
4 /*
5  * Doxygen can't cope with some of the more esoteric areas of C, so we
6  * make its life simpler.
7  *
8  */
9 #ifdef DOXYGEN
10 #define __attribute__(x)
11 #endif
12 
13 /** @file
14  *
15  * Global compiler definitions.
16  *
17  * This file is implicitly included by every @c .c file in Etherboot.
18  * It defines global macros such as DBG().
19  *
20  * We arrange for each object to export the symbol @c obj_OBJECT
21  * (where @c OBJECT is the object name, e.g. @c rtl8139) as a global
22  * symbol, so that the linker can drag in selected object files from
23  * the library using <tt> -u obj_OBJECT </tt>.
24  *
25  */
26 
27 /* Force visibility of all symbols to "hidden", i.e. inform gcc that
28  * all symbol references resolve strictly within our final binary.
29  * This avoids unnecessary PLT/GOT entries on x86_64.
30  *
31  * This is a stronger claim than specifying "-fvisibility=hidden",
32  * since it also affects symbols marked with "extern".
33  */
34 #ifndef ASSEMBLY
35 #if __GNUC__ >= 4
36 #pragma GCC visibility push(hidden)
37 #endif
38 #endif /* ASSEMBLY */
39 
40 #undef _S1
41 #undef _S2
42 #undef _C1
43 #undef _C2
44 
45 /** Concatenate non-expanded arguments */
46 #define _C1( x, y ) x ## y
47 /** Concatenate expanded arguments */
48 #define _C2( x, y ) _C1 ( x, y )
49 
50 /** Stringify non-expanded argument */
51 #define _S1( x ) #x
52 /** Stringify expanded argument */
53 #define _S2( x ) _S1 ( x )
54 
55 /* Assembler section types */
56 #ifdef ASSEMBLY
57 #define PROGBITS _C2 ( ASM_TCHAR, progbits )
58 #define NOBITS _C2 ( ASM_TCHAR, nobits )
59 #else
60 #define PROGBITS_OPS _S2 ( ASM_TCHAR_OPS ) "progbits"
61 #define PROGBITS _S2 ( ASM_TCHAR ) "progbits"
62 #define NOBITS_OPS _S2 ( ASM_TCHAR_OPS ) "nobits"
63 #define NOBITS _S2 ( ASM_TCHAR ) "nobits"
64 #endif
65 
66 /**
67  * @defgroup symmacros Macros to provide or require explicit symbols
68  * @{
69  */
70 
71 /**
72  * Provide a symbol within this object file
73  *
74  * @v symbol		Symbol name
75  */
76 #ifdef ASSEMBLY
77 #define PROVIDE_SYMBOL( symbol )				\
78 	.section ".provided", "a", NOBITS ;			\
79 	.hidden symbol ;					\
80 	.globl	symbol ;					\
81 	symbol: ;						\
82 	.previous
83 #else
84 #define PROVIDE_SYMBOL( symbol )				\
85 	char symbol[0]						\
86 	  __attribute__ (( section ( ".provided" ) ))
87 #endif
88 
89 /**
90  * Request a symbol
91  *
92  * @v symbol		Symbol name
93  *
94  * Request a symbol to be included within the link.  If the symbol
95  * cannot be found, the link will succeed anyway.
96  */
97 #ifdef ASSEMBLY
98 #define REQUEST_SYMBOL( symbol )				\
99 	.equ __request_ ## symbol, symbol
100 #else
101 #define REQUEST_SYMBOL( symbol )				\
102 	__asm__ ( ".equ __request_" #symbol ", " #symbol )
103 #endif
104 
105 /**
106  * Require a symbol
107  *
108  * @v symbol		Symbol name
109  *
110  * Require a symbol to be included within the link.  If the symbol
111  * cannot be found, the link will fail.
112  *
113  * To use this macro within a file, you must also specify the file's
114  * "requiring symbol" using the REQUIRING_SYMBOL() or
115  * PROVIDE_REQUIRING_SYMBOL() macros.
116  */
117 #ifdef ASSEMBLY
118 #define REQUIRE_SYMBOL( symbol )				\
119 	.reloc __requiring_symbol__, RELOC_TYPE_NONE, symbol
120 #else
121 #define REQUIRE_SYMBOL( symbol )				\
122 	__asm__ ( ".reloc __requiring_symbol__, "		\
123 		  _S2 ( RELOC_TYPE_NONE ) ", " #symbol )
124 #endif
125 
126 /**
127  * Specify the file's requiring symbol
128  *
129  * @v symbol		Symbol name
130  *
131  * REQUIRE_SYMBOL() works by defining a dummy relocation record
132  * against a nominated "requiring symbol".  The presence of the
133  * nominated requiring symbol will drag in all of the symbols
134  * specified using REQUIRE_SYMBOL().
135  */
136 #ifdef ASSEMBLY
137 #define REQUIRING_SYMBOL( symbol )				\
138 	.equ __requiring_symbol__, symbol
139 #else
140 #define REQUIRING_SYMBOL( symbol )				\
141 	__asm__ ( ".equ __requiring_symbol__, " #symbol )
142 #endif
143 
144 /**
145  * Provide a file's requiring symbol
146  *
147  * If the file contains no symbols that can be used as the requiring
148  * symbol, you can provide a dummy one-byte-long symbol using
149  * PROVIDE_REQUIRING_SYMBOL().
150  */
151 #ifdef ASSEMBLY
152 #define PROVIDE_REQUIRING_SYMBOL()				\
153 	.section ".tbl.requiring_symbols", "a", PROGBITS ;	\
154 	__requiring_symbol__:	.byte 0 ;			\
155 	.size __requiring_symbol__, . - __requiring_symbol__ ;	\
156 	.previous
157 #else
158 #define PROVIDE_REQUIRING_SYMBOL()				\
159 	__asm__ ( ".section \".tbl.requiring_symbols\", "	\
160 		  "         \"a\", " PROGBITS "\n"		\
161 		  "__requiring_symbol__:\t.byte 0\n"		\
162 		  ".size __requiring_symbol__, "		\
163 		  "      . - __requiring_symbol__\n"		\
164 		  ".previous" )
165 #endif
166 
167 /** @} */
168 
169 /**
170  * @defgroup objmacros Macros to provide or require explicit objects
171  * @{
172  */
173 
174 #define PREFIX_OBJECT( _prefix ) _C2 ( _prefix, OBJECT )
175 #define OBJECT_SYMBOL PREFIX_OBJECT ( obj_ )
176 
177 /** Always provide the symbol for the current object (defined by -DOBJECT) */
178 PROVIDE_SYMBOL ( OBJECT_SYMBOL );
179 
180 /**
181  * Request an object
182  *
183  * @v object		Object name
184  *
185  * Request an object to be included within the link.  If the object
186  * cannot be found, the link will succeed anyway.
187  */
188 #define REQUEST_OBJECT( object ) REQUEST_SYMBOL ( obj_ ## object )
189 
190 /**
191  * Require an object
192  *
193  * @v object		Object name
194  *
195  * Require an object to be included within the link.  If the object
196  * cannot be found, the link will fail.
197  *
198  * To use this macro within a file, you must also specify the file's
199  * "requiring symbol" using the REQUIRING_SYMBOL() or
200  * PROVIDE_REQUIRING_SYMBOL() macros.
201  */
202 #define REQUIRE_OBJECT( object ) REQUIRE_SYMBOL ( obj_ ## object )
203 
204 /** @} */
205 
206 /** Select file identifier for errno.h (if used) */
207 #define ERRFILE PREFIX_OBJECT ( ERRFILE_ )
208 
209 #ifndef ASSEMBLY
210 
211 /** Declare a function as weak (use *before* the definition)
212  *
213  * Due to a bug in at least GCC 4.4.4 and earlier, weak symbols may be
214  * inlined if they have hidden visibility (see above for why hidden
215  * visibility is used).  This results in the non-weak symbol never
216  * being used, so explicitly mark the function as noinline to prevent
217  * inlining.
218  */
219 #define __weak		__attribute__ (( weak, noinline ))
220 
221 #endif
222 
223 /** @defgroup dbg Debugging infrastructure
224  * @{
225  */
226 
227 /** @def DBG
228  *
229  * Print a debugging message.
230  *
231  * The debug level is set at build time by specifying the @c DEBUG=
232  * parameter on the @c make command line.  For example, to enable
233  * debugging for the PCI bus functions (in pci.c) in a @c .dsk image
234  * for the @c rtl8139 card, you could use the command line
235  *
236  * @code
237  *
238  *   make bin/rtl8139.dsk DEBUG=pci
239  *
240  * @endcode
241  *
242  * This will enable the debugging statements (DBG()) in pci.c.  If
243  * debugging is not enabled, DBG() statements will be ignored.
244  *
245  * You can enable debugging in several objects simultaneously by
246  * separating them with commas, as in
247  *
248  * @code
249  *
250  *   make bin/rtl8139.dsk DEBUG=pci,buffer,heap
251  *
252  * @endcode
253  *
254  * You can increase the debugging level for an object by specifying it
255  * with @c :N, where @c N is the level, as in
256  *
257  * @code
258  *
259  *   make bin/rtl8139.dsk DEBUG=pci,buffer:2,heap
260  *
261  * @endcode
262  *
263  * which would enable debugging for the PCI, buffer-handling and
264  * heap-allocation code, with the buffer-handling code at level 2.
265  *
266  */
267 
268 #ifndef DBGLVL_MAX
269 #define NDEBUG
270 #define DBGLVL_MAX 0
271 #endif
272 
273 #ifndef DBGLVL_DFLT
274 #define DBGLVL_DFLT DBGLVL_MAX
275 #endif
276 
277 #ifndef ASSEMBLY
278 
279 /** printf() for debugging */
280 extern void __attribute__ (( format ( printf, 1, 2 ) ))
281 dbg_printf ( const char *fmt, ... );
282 extern void dbg_autocolourise ( unsigned long id );
283 extern void dbg_decolourise ( void );
284 extern void dbg_hex_dump_da ( unsigned long dispaddr,
285 			      const void *data, unsigned long len );
286 extern void dbg_md5_da ( unsigned long dispaddr,
287 			 const void *data, unsigned long len );
288 extern void dbg_pause ( void );
289 extern void dbg_more ( void );
290 
291 /* Allow for selective disabling of enabled debug levels */
292 #define __debug_disable( object ) _C2 ( __debug_disable_, object )
293 char __debug_disable(OBJECT) = ( DBGLVL_MAX & ~DBGLVL_DFLT );
294 #define DBG_DISABLE_OBJECT( object, level ) do {		\
295 	extern char __debug_disable(object);			\
296 	__debug_disable(object) |= (level);			\
297 	} while ( 0 )
298 #define DBG_ENABLE_OBJECT( object, level ) do {			\
299 	extern char __debug_disable(object);			\
300 	__debug_disable(object) &= ~(level);			\
301 	} while ( 0 )
302 #if DBGLVL_MAX
303 #define DBGLVL ( DBGLVL_MAX & ~__debug_disable(OBJECT) )
304 #define DBG_DISABLE( level ) do {				\
305 	__debug_disable(OBJECT) |= ( (level) & DBGLVL_MAX );	\
306 	} while ( 0 )
307 #define DBG_ENABLE( level ) do {				\
308 	__debug_disable(OBJECT) &= ~( (level) & DBGLVL_MAX );	\
309 	} while ( 0 )
310 #else
311 #define DBGLVL 0
312 #define DBG_DISABLE( level ) do { } while ( 0 )
313 #define DBG_ENABLE( level ) do { } while ( 0 )
314 #endif
315 
316 #define DBGLVL_LOG	1
317 #define DBG_LOG		( DBGLVL & DBGLVL_LOG )
318 #define DBGLVL_EXTRA	2
319 #define DBG_EXTRA	( DBGLVL & DBGLVL_EXTRA )
320 #define DBGLVL_PROFILE	4
321 #define DBG_PROFILE	( DBGLVL & DBGLVL_PROFILE )
322 #define DBGLVL_IO	8
323 #define DBG_IO		( DBGLVL & DBGLVL_IO )
324 
325 /**
326  * Print debugging message if we are at a certain debug level
327  *
328  * @v level		Debug level
329  * @v ...		printf() argument list
330  */
331 #define DBG_IF( level, ... ) do {				\
332 		if ( DBG_ ## level ) {				\
333 			dbg_printf ( __VA_ARGS__ );		\
334 		}						\
335 	} while ( 0 )
336 
337 /**
338  * Print a hex dump if we are at a certain debug level
339  *
340  * @v level		Debug level
341  * @v dispaddr		Display address
342  * @v data		Data to print
343  * @v len		Length of data
344  */
345 #define DBG_HDA_IF( level, dispaddr, data, len )  do {		\
346 		if ( DBG_ ## level ) {				\
347 			union {					\
348 				unsigned long ul;		\
349 				typeof ( dispaddr ) raw;	\
350 			} da;					\
351 			da.ul = 0;				\
352 			da.raw = dispaddr;			\
353 			dbg_hex_dump_da ( da.ul, data, len );	\
354 		}						\
355 	} while ( 0 )
356 
357 /**
358  * Print a hex dump if we are at a certain debug level
359  *
360  * @v level		Debug level
361  * @v data		Data to print
362  * @v len		Length of data
363  */
364 #define DBG_HD_IF( level, data, len ) do {			\
365 		const void *_data = data;			\
366 		DBG_HDA_IF ( level, _data, _data, len );	\
367 	} while ( 0 )
368 
369 /**
370  * Print an MD5 checksum if we are at a certain debug level
371  *
372  * @v level		Debug level
373  * @v dispaddr		Display address
374  * @v data		Data to print
375  * @v len		Length of data
376  */
377 #define DBG_MD5A_IF( level, dispaddr, data, len )  do {		\
378 		if ( DBG_ ## level ) {				\
379 			union {					\
380 				unsigned long ul;		\
381 				typeof ( dispaddr ) raw;	\
382 			} da;					\
383 			da.ul = 0;				\
384 			da.raw = dispaddr;			\
385 			dbg_md5_da ( da.ul, data, len );	\
386 		}						\
387 	} while ( 0 )
388 
389 /**
390  * Print an MD5 checksum if we are at a certain debug level
391  *
392  * @v level		Debug level
393  * @v data		Data to print
394  * @v len		Length of data
395  */
396 #define DBG_MD5_IF( level, data, len ) do {			\
397 		const void *_data = data;			\
398 		DBG_MD5A_IF ( level, _data, _data, len );	\
399 	} while ( 0 )
400 
401 /**
402  * Prompt for key press if we are at a certain debug level
403  *
404  * @v level		Debug level
405  */
406 #define DBG_PAUSE_IF( level, ... ) do {				\
407 		if ( DBG_ ## level ) {				\
408 			dbg_pause();				\
409 		}						\
410 	} while ( 0 )
411 
412 /**
413  * Prompt for more output data if we are at a certain debug level
414  *
415  * @v level		Debug level
416  */
417 #define DBG_MORE_IF( level, ... ) do {				\
418 		if ( DBG_ ## level ) {				\
419 			dbg_more();				\
420 		}						\
421 	} while ( 0 )
422 
423 /**
424  * Select colour for debug messages if we are at a certain debug level
425  *
426  * @v level		Debug level
427  * @v id		Message stream ID
428  */
429 #define DBG_AC_IF( level, id ) do {				\
430 		if ( DBG_ ## level ) {				\
431 			union {					\
432 				unsigned long ul;		\
433 				typeof ( id ) raw;		\
434 			} dbg_stream;				\
435 			dbg_stream.ul = 0;			\
436 			dbg_stream.raw = id;			\
437 			dbg_autocolourise ( dbg_stream.ul );	\
438 		}						\
439 	} while ( 0 )
440 
441 /**
442  * Revert colour for debug messages if we are at a certain debug level
443  *
444  * @v level		Debug level
445  */
446 #define DBG_DC_IF( level ) do {					\
447 		if ( DBG_ ## level ) {				\
448 			dbg_decolourise();			\
449 		}						\
450 	} while ( 0 )
451 
452 /* Autocolourising versions of the DBGxxx_IF() macros */
453 
454 #define DBGC_IF( level, id, ... ) do {				\
455 		DBG_AC_IF ( level, id );			\
456 		DBG_IF ( level, __VA_ARGS__ );			\
457 		DBG_DC_IF ( level );				\
458 	} while ( 0 )
459 
460 #define DBGC_HDA_IF( level, id, ... ) do {			\
461 		DBG_AC_IF ( level, id );			\
462 		DBG_HDA_IF ( level, __VA_ARGS__ );		\
463 		DBG_DC_IF ( level );				\
464 	} while ( 0 )
465 
466 #define DBGC_HD_IF( level, id, ... ) do {			\
467 		DBG_AC_IF ( level, id );			\
468 		DBG_HD_IF ( level, __VA_ARGS__ );		\
469 		DBG_DC_IF ( level );				\
470 	} while ( 0 )
471 
472 #define DBGC_MD5A_IF( level, id, ... ) do {			\
473 		DBG_AC_IF ( level, id );			\
474 		DBG_MD5A_IF ( level, __VA_ARGS__ );		\
475 		DBG_DC_IF ( level );				\
476 	} while ( 0 )
477 
478 #define DBGC_MD5_IF( level, id, ... ) do {			\
479 		DBG_AC_IF ( level, id );			\
480 		DBG_MD5_IF ( level, __VA_ARGS__ );		\
481 		DBG_DC_IF ( level );				\
482 	} while ( 0 )
483 
484 #define DBGC_PAUSE_IF( level, id ) do {				\
485 		DBG_AC_IF ( level, id );			\
486 		DBG_PAUSE_IF ( level );				\
487 		DBG_DC_IF ( level );				\
488 	} while ( 0 )
489 
490 #define DBGC_MORE_IF( level, id ) do {				\
491 		DBG_AC_IF ( level, id );			\
492 		DBG_MORE_IF ( level );				\
493 		DBG_DC_IF ( level );				\
494 	} while ( 0 )
495 
496 /* Versions of the DBGxxx_IF() macros that imply DBGxxx_IF( LOG, ... )*/
497 
498 #define DBG( ... )		DBG_IF		( LOG, ##__VA_ARGS__ )
499 #define DBG_HDA( ... )		DBG_HDA_IF	( LOG, ##__VA_ARGS__ )
500 #define DBG_HD( ... )		DBG_HD_IF	( LOG, ##__VA_ARGS__ )
501 #define DBG_MD5A( ... )		DBG_MD5A_IF	( LOG, ##__VA_ARGS__ )
502 #define DBG_MD5( ... )		DBG_MD5_IF	( LOG, ##__VA_ARGS__ )
503 #define DBG_PAUSE( ... )	DBG_PAUSE_IF	( LOG, ##__VA_ARGS__ )
504 #define DBG_MORE( ... )		DBG_MORE_IF	( LOG, ##__VA_ARGS__ )
505 #define DBGC( ... )		DBGC_IF		( LOG, ##__VA_ARGS__ )
506 #define DBGC_HDA( ... )		DBGC_HDA_IF	( LOG, ##__VA_ARGS__ )
507 #define DBGC_HD( ... )		DBGC_HD_IF	( LOG, ##__VA_ARGS__ )
508 #define DBGC_MD5A( ... )	DBGC_MD5A_IF	( LOG, ##__VA_ARGS__ )
509 #define DBGC_MD5( ... )		DBGC_MD5_IF	( LOG, ##__VA_ARGS__ )
510 #define DBGC_PAUSE( ... )	DBGC_PAUSE_IF	( LOG, ##__VA_ARGS__ )
511 #define DBGC_MORE( ... )	DBGC_MORE_IF	( LOG, ##__VA_ARGS__ )
512 
513 /* Versions of the DBGxxx_IF() macros that imply DBGxxx_IF( EXTRA, ... )*/
514 
515 #define DBG2( ... )		DBG_IF		( EXTRA, ##__VA_ARGS__ )
516 #define DBG2_HDA( ... )		DBG_HDA_IF	( EXTRA, ##__VA_ARGS__ )
517 #define DBG2_HD( ... )		DBG_HD_IF	( EXTRA, ##__VA_ARGS__ )
518 #define DBG2_MD5A( ... )	DBG_MD5A_IF	( EXTRA, ##__VA_ARGS__ )
519 #define DBG2_MD5( ... )		DBG_MD5_IF	( EXTRA, ##__VA_ARGS__ )
520 #define DBG2_PAUSE( ... )	DBG_PAUSE_IF	( EXTRA, ##__VA_ARGS__ )
521 #define DBG2_MORE( ... )	DBG_MORE_IF	( EXTRA, ##__VA_ARGS__ )
522 #define DBGC2( ... )		DBGC_IF		( EXTRA, ##__VA_ARGS__ )
523 #define DBGC2_HDA( ... )	DBGC_HDA_IF	( EXTRA, ##__VA_ARGS__ )
524 #define DBGC2_HD( ... )		DBGC_HD_IF	( EXTRA, ##__VA_ARGS__ )
525 #define DBGC2_MD5A( ... )	DBGC_MD5A_IF	( EXTRA, ##__VA_ARGS__ )
526 #define DBGC2_MD5( ... )	DBGC_MD5_IF	( EXTRA, ##__VA_ARGS__ )
527 #define DBGC2_PAUSE( ... )	DBGC_PAUSE_IF	( EXTRA, ##__VA_ARGS__ )
528 #define DBGC2_MORE( ... )	DBGC_MORE_IF	( EXTRA, ##__VA_ARGS__ )
529 
530 /* Versions of the DBGxxx_IF() macros that imply DBGxxx_IF( PROFILE, ... )*/
531 
532 #define DBGP( ... )		DBG_IF		( PROFILE, ##__VA_ARGS__ )
533 #define DBGP_HDA( ... )		DBG_HDA_IF	( PROFILE, ##__VA_ARGS__ )
534 #define DBGP_HD( ... )		DBG_HD_IF	( PROFILE, ##__VA_ARGS__ )
535 #define DBGP_MD5A( ... )	DBG_MD5A_IF	( PROFILE, ##__VA_ARGS__ )
536 #define DBGP_MD5( ... )		DBG_MD5_IF	( PROFILE, ##__VA_ARGS__ )
537 #define DBGP_PAUSE( ... )	DBG_PAUSE_IF	( PROFILE, ##__VA_ARGS__ )
538 #define DBGP_MORE( ... )	DBG_MORE_IF	( PROFILE, ##__VA_ARGS__ )
539 #define DBGCP( ... )		DBGC_IF		( PROFILE, ##__VA_ARGS__ )
540 #define DBGCP_HDA( ... )	DBGC_HDA_IF	( PROFILE, ##__VA_ARGS__ )
541 #define DBGCP_HD( ... )		DBGC_HD_IF	( PROFILE, ##__VA_ARGS__ )
542 #define DBGCP_MD5A( ... )	DBGC_MD5A_IF	( PROFILE, ##__VA_ARGS__ )
543 #define DBGCP_MD5( ... )	DBGC_MD5_IF	( PROFILE, ##__VA_ARGS__ )
544 #define DBGCP_PAUSE( ... )	DBGC_PAUSE_IF	( PROFILE, ##__VA_ARGS__ )
545 #define DBGCP_MORE( ... )	DBGC_MORE_IF	( PROFILE, ##__VA_ARGS__ )
546 
547 /* Versions of the DBGxxx_IF() macros that imply DBGxxx_IF( IO, ... )*/
548 
549 #define DBGIO( ... )		DBG_IF		( IO, ##__VA_ARGS__ )
550 #define DBGIO_HDA( ... )	DBG_HDA_IF	( IO, ##__VA_ARGS__ )
551 #define DBGIO_HD( ... )		DBG_HD_IF	( IO, ##__VA_ARGS__ )
552 #define DBGIO_MD5A( ... )	DBG_MD5A_IF	( IO, ##__VA_ARGS__ )
553 #define DBGIO_MD5( ... )	DBG_MD5_IF	( IO, ##__VA_ARGS__ )
554 #define DBGIO_PAUSE( ... )	DBG_PAUSE_IF	( IO, ##__VA_ARGS__ )
555 #define DBGIO_MORE( ... )	DBG_MORE_IF	( IO, ##__VA_ARGS__ )
556 #define DBGCIO( ... )		DBGC_IF		( IO, ##__VA_ARGS__ )
557 #define DBGCIO_HDA( ... )	DBGC_HDA_IF	( IO, ##__VA_ARGS__ )
558 #define DBGCIO_HD( ... )	DBGC_HD_IF	( IO, ##__VA_ARGS__ )
559 #define DBGCIO_MD5A( ... )	DBGC_MD5A_IF	( IO, ##__VA_ARGS__ )
560 #define DBGCIO_MD5( ... )	DBGC_MD5_IF	( IO, ##__VA_ARGS__ )
561 #define DBGCIO_PAUSE( ... )	DBGC_PAUSE_IF	( IO, ##__VA_ARGS__ )
562 #define DBGCIO_MORE( ... )	DBGC_MORE_IF	( IO, ##__VA_ARGS__ )
563 
564 #endif /* ASSEMBLY */
565 /** @} */
566 
567 /** @defgroup attrs Miscellaneous attributes
568  * @{
569  */
570 #ifndef ASSEMBLY
571 
572 /** Declare a variable or data structure as unused. */
573 #define __unused __attribute__ (( unused ))
574 
575 /**
576  * Declare a function as pure - i.e. without side effects
577  */
578 #define __pure __attribute__ (( pure ))
579 
580 /**
581  * Declare a function as const - i.e. it does not access global memory
582  * (including dereferencing pointers passed to it) at all.
583  * Must also not call any non-const functions.
584  */
585 #define __const __attribute__ (( const ))
586 
587 /**
588  * Declare a function's pointer parameters as non-null - i.e. force
589  * compiler to check pointers at compile time and enable possible
590  * optimizations based on that fact
591  */
592 #define __nonnull __attribute__ (( nonnull ))
593 
594 /**
595  * Declare a pointer returned by a function as a unique memory address
596  * as returned by malloc-type functions.
597  */
598 #define __malloc __attribute__ (( malloc ))
599 
600 /**
601  * Declare a function as used.
602  *
603  * Necessary only if the function is called only from assembler code.
604  */
605 #define __used __attribute__ (( used ))
606 
607 /** Declare a data structure to be aligned with 16-byte alignment */
608 #define __aligned __attribute__ (( aligned ( 16 ) ))
609 
610 /** Declare a function to be always inline */
611 #define __always_inline __attribute__ (( always_inline ))
612 
613 /* Force all inline functions to not be instrumented
614  *
615  * This is required to cope with what seems to be a long-standing gcc
616  * bug, in which -finstrument-functions will cause instances of
617  * inlined functions to be reported as further calls to the
618  * *containing* function.  This makes instrumentation very difficult
619  * to use.
620  *
621  * Work around this problem by adding the no_instrument_function
622  * attribute to all inlined functions.
623  */
624 #define inline inline __attribute__ (( no_instrument_function ))
625 
626 /**
627  * Shared data.
628  *
629  * To save space in the binary when multiple-driver images are
630  * compiled, uninitialised data areas can be shared between drivers.
631  * This will typically be used to share statically-allocated receive
632  * and transmit buffers between drivers.
633  *
634  * Use as e.g.
635  *
636  * @code
637  *
638  *   struct {
639  *	char	rx_buf[NUM_RX_BUF][RX_BUF_SIZE];
640  *	char	tx_buf[TX_BUF_SIZE];
641  *   } my_static_data __shared;
642  *
643  * @endcode
644  *
645  */
646 #define __shared __asm__ ( "_shared_bss" ) __aligned
647 
648 #endif /* ASSEMBLY */
649 /** @} */
650 
651 /**
652  * Optimisation barrier
653  */
654 #ifndef ASSEMBLY
655 #define barrier() __asm__ __volatile__ ( "" : : : "memory" )
656 #endif /* ASSEMBLY */
657 
658 /**
659  * Array size
660  */
661 #ifndef ASSEMBLY
662 #define ARRAY_SIZE(array) ( sizeof (array) / sizeof ( (array)[0] ) )
663 #endif /* ASSEMBLY */
664 
665 /**
666  * @defgroup licences Licence declarations
667  *
668  * For reasons that are partly historical, various different files
669  * within the iPXE codebase have differing licences.
670  *
671  * @{
672  */
673 
674 /** Declare a file as being in the public domain
675  *
676  * This licence declaration is applicable when a file states itself to
677  * be in the public domain.
678  */
679 #define FILE_LICENCE_PUBLIC_DOMAIN \
680 	PROVIDE_SYMBOL ( PREFIX_OBJECT ( __licence__public_domain__ ) )
681 
682 /** Declare a file as being under version 2 (or later) of the GNU GPL
683  *
684  * This licence declaration is applicable when a file states itself to
685  * be licensed under the GNU GPL; "either version 2 of the License, or
686  * (at your option) any later version".
687  */
688 #define FILE_LICENCE_GPL2_OR_LATER \
689 	PROVIDE_SYMBOL ( PREFIX_OBJECT ( __licence__gpl2_or_later__ ) )
690 
691 /** Declare a file as being under version 2 of the GNU GPL
692  *
693  * This licence declaration is applicable when a file states itself to
694  * be licensed under version 2 of the GPL, and does not include the
695  * "or, at your option, any later version" clause.
696  */
697 #define FILE_LICENCE_GPL2_ONLY \
698 	PROVIDE_SYMBOL ( PREFIX_OBJECT ( __licence__gpl2_only__ ) )
699 
700 /** Declare a file as being under any version of the GNU GPL
701  *
702  * This licence declaration is applicable when a file states itself to
703  * be licensed under the GPL, but does not specify a version.
704  *
705  * According to section 9 of the GPLv2, "If the Program does not
706  * specify a version number of this License, you may choose any
707  * version ever published by the Free Software Foundation".
708  */
709 #define FILE_LICENCE_GPL_ANY \
710 	PROVIDE_SYMBOL ( PREFIX_OBJECT ( __licence__gpl_any__ ) )
711 
712 /** Declare a file as being under the three-clause BSD licence
713  *
714  * This licence declaration is applicable when a file states itself to
715  * be licensed under terms allowing redistribution in source and
716  * binary forms (with or without modification) provided that:
717  *
718  *     redistributions of source code retain the copyright notice,
719  *     list of conditions and any attached disclaimers
720  *
721  *     redistributions in binary form reproduce the copyright notice,
722  *     list of conditions and any attached disclaimers in the
723  *     documentation and/or other materials provided with the
724  *     distribution
725  *
726  *     the name of the author is not used to endorse or promote
727  *     products derived from the software without specific prior
728  *     written permission
729  *
730  * It is not necessary for the file to explicitly state that it is
731  * under a "BSD" licence; only that the licensing terms be
732  * functionally equivalent to the standard three-clause BSD licence.
733  */
734 #define FILE_LICENCE_BSD3 \
735 	PROVIDE_SYMBOL ( PREFIX_OBJECT ( __licence__bsd3__ ) )
736 
737 /** Declare a file as being under the two-clause BSD licence
738  *
739  * This licence declaration is applicable when a file states itself to
740  * be licensed under terms allowing redistribution in source and
741  * binary forms (with or without modification) provided that:
742  *
743  *     redistributions of source code retain the copyright notice,
744  *     list of conditions and any attached disclaimers
745  *
746  *     redistributions in binary form reproduce the copyright notice,
747  *     list of conditions and any attached disclaimers in the
748  *     documentation and/or other materials provided with the
749  *     distribution
750  *
751  * It is not necessary for the file to explicitly state that it is
752  * under a "BSD" licence; only that the licensing terms be
753  * functionally equivalent to the standard two-clause BSD licence.
754  */
755 #define FILE_LICENCE_BSD2 \
756 	PROVIDE_SYMBOL ( PREFIX_OBJECT ( __licence__bsd2__ ) )
757 
758 /** Declare a file as being under the one-clause MIT-style licence
759  *
760  * This licence declaration is applicable when a file states itself to
761  * be licensed under terms allowing redistribution for any purpose
762  * with or without fee, provided that the copyright notice and
763  * permission notice appear in all copies.
764  */
765 #define FILE_LICENCE_MIT \
766 	PROVIDE_SYMBOL ( PREFIX_OBJECT ( __licence__mit__ ) )
767 
768 /** Declare a file as being under GPLv2+ or UBDL
769  *
770  * This licence declaration is applicable when a file states itself to
771  * be licensed under the GNU GPL; "either version 2 of the License, or
772  * (at your option) any later version" and also states that it may be
773  * distributed under the terms of the Unmodified Binary Distribution
774  * Licence (as given in the file COPYING.UBDL).
775  */
776 #define FILE_LICENCE_GPL2_OR_LATER_OR_UBDL \
777 	PROVIDE_SYMBOL ( PREFIX_OBJECT ( __licence__gpl2_or_later_or_ubdl__ ) )
778 
779 /** Declare a particular licence as applying to a file */
780 #define FILE_LICENCE( _licence ) FILE_LICENCE_ ## _licence
781 
782 /** @} */
783 
784 /* This file itself is under GPLv2+/UBDL */
785 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
786 
787 #include <bits/compiler.h>
788 
789 #endif /* COMPILER_H */
790