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authorYang Zhang <yang.z.zhang@intel.com>2015-08-28 09:58:54 +0800
committerYang Zhang <yang.z.zhang@intel.com>2015-09-01 12:44:00 +0800
commite44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch)
tree66b09f592c55df2878107a468a91d21506104d3f /qemu/roms/ipxe/src/include/compiler.h
parent9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff)
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/roms/ipxe/src/include/compiler.h')
-rw-r--r--qemu/roms/ipxe/src/include/compiler.h743
1 files changed, 743 insertions, 0 deletions
diff --git a/qemu/roms/ipxe/src/include/compiler.h b/qemu/roms/ipxe/src/include/compiler.h
new file mode 100644
index 000000000..3f5c913a0
--- /dev/null
+++ b/qemu/roms/ipxe/src/include/compiler.h
@@ -0,0 +1,743 @@
+#ifndef COMPILER_H
+#define COMPILER_H
+
+/*
+ * Doxygen can't cope with some of the more esoteric areas of C, so we
+ * make its life simpler.
+ *
+ */
+#ifdef DOXYGEN
+#define __attribute__(x)
+#endif
+
+/** @file
+ *
+ * Global compiler definitions.
+ *
+ * This file is implicitly included by every @c .c file in Etherboot.
+ * It defines global macros such as DBG().
+ *
+ * We arrange for each object to export the symbol @c obj_OBJECT
+ * (where @c OBJECT is the object name, e.g. @c rtl8139) as a global
+ * symbol, so that the linker can drag in selected object files from
+ * the library using <tt> -u obj_OBJECT </tt>.
+ *
+ */
+
+/* Force visibility of all symbols to "hidden", i.e. inform gcc that
+ * all symbol references resolve strictly within our final binary.
+ * This avoids unnecessary PLT/GOT entries on x86_64.
+ *
+ * This is a stronger claim than specifying "-fvisibility=hidden",
+ * since it also affects symbols marked with "extern".
+ */
+#ifndef ASSEMBLY
+#if __GNUC__ >= 4
+#pragma GCC visibility push(hidden)
+#endif
+#endif /* ASSEMBLY */
+
+#undef _S1
+#undef _S2
+#undef _C1
+#undef _C2
+
+/** Concatenate non-expanded arguments */
+#define _C1( x, y ) x ## y
+/** Concatenate expanded arguments */
+#define _C2( x, y ) _C1 ( x, y )
+
+/** Stringify non-expanded argument */
+#define _S1( x ) #x
+/** Stringify expanded argument */
+#define _S2( x ) _S1 ( x )
+
+/**
+ * @defgroup symmacros Macros to provide or require explicit symbols
+ * @{
+ */
+
+/** Provide a symbol within this object file */
+#ifdef ASSEMBLY
+#define PROVIDE_SYMBOL( _sym ) \
+ .section ".provided", "a", @nobits ; \
+ .hidden _sym ; \
+ .globl _sym ; \
+ _sym: ; \
+ .previous
+#else /* ASSEMBLY */
+#define PROVIDE_SYMBOL( _sym ) \
+ char _sym[0] \
+ __attribute__ (( section ( ".provided" ) ))
+#endif /* ASSEMBLY */
+
+/** Require a symbol within this object file
+ *
+ * The symbol is referenced by a relocation in a discarded section, so
+ * if it is not available at link time the link will fail.
+ */
+#ifdef ASSEMBLY
+#define REQUIRE_SYMBOL( _sym ) \
+ .section ".discard", "a", @progbits ; \
+ .extern _sym ; \
+ .long _sym ; \
+ .previous
+#else /* ASSEMBLY */
+#define REQUIRE_SYMBOL( _sym ) \
+ extern char _sym; \
+ static char * _C2 ( _C2 ( __require_, _sym ), _C2 ( _, __LINE__ ) ) \
+ __attribute__ (( section ( ".discard" ), used )) \
+ = &_sym
+#endif
+
+/** Request that a symbol be available at runtime
+ *
+ * The requested symbol is entered as undefined into the symbol table
+ * for this object, so the linker will pull in other object files as
+ * necessary to satisfy the reference. However, the undefined symbol
+ * is not referenced in any relocations, so the link can still succeed
+ * if no file contains it.
+ *
+ * A symbol passed to this macro may not be referenced anywhere
+ * else in the file. If you want to do that, see IMPORT_SYMBOL().
+ */
+#ifdef ASSEMBLY
+#define REQUEST_SYMBOL( _sym ) \
+ .equ __need_ ## _sym, _sym
+#else /* ASSEMBLY */
+#define REQUEST_SYMBOL( _sym ) \
+ __asm__ ( ".equ\t__need_" #_sym ", " #_sym )
+#endif /* ASSEMBLY */
+
+/** Set up a symbol to be usable in another file by IMPORT_SYMBOL()
+ *
+ * The symbol must already be marked as global.
+ */
+#define EXPORT_SYMBOL( _sym ) PROVIDE_SYMBOL ( __export_ ## _sym )
+
+/** Make a symbol usable to this file if available at link time
+ *
+ * If no file passed to the linker contains the symbol, it will have
+ * @c NULL value to future uses. Keep in mind that the symbol value is
+ * really the @e address of a variable or function; see the code
+ * snippet below.
+ *
+ * In C using IMPORT_SYMBOL, you must specify the declaration as the
+ * second argument, for instance
+ *
+ * @code
+ * IMPORT_SYMBOL ( my_func, int my_func ( int arg ) );
+ * IMPORT_SYMBOL ( my_var, int my_var );
+ *
+ * void use_imports ( void ) {
+ * if ( my_func && &my_var )
+ * my_var = my_func ( my_var );
+ * }
+ * @endcode
+ *
+ * GCC considers a weak declaration to override a strong one no matter
+ * which comes first, so it is safe to include a header file declaring
+ * the imported symbol normally, but providing the declaration to
+ * IMPORT_SYMBOL is still required.
+ *
+ * If no EXPORT_SYMBOL declaration exists for the imported symbol in
+ * another file, the behavior will be most likely be identical to that
+ * for an unavailable symbol.
+ */
+#ifdef ASSEMBLY
+#define IMPORT_SYMBOL( _sym ) \
+ REQUEST_SYMBOL ( __export_ ## _sym ) ; \
+ .weak _sym
+#else /* ASSEMBLY */
+#define IMPORT_SYMBOL( _sym, _decl ) \
+ REQUEST_SYMBOL ( __export_ ## _sym ) ; \
+ extern _decl __attribute__ (( weak ))
+#endif
+
+/** @} */
+
+/**
+ * @defgroup objmacros Macros to provide or require explicit objects
+ * @{
+ */
+
+#define PREFIX_OBJECT( _prefix ) _C2 ( _prefix, OBJECT )
+#define OBJECT_SYMBOL PREFIX_OBJECT ( obj_ )
+#define REQUEST_EXPANDED( _sym ) REQUEST_SYMBOL ( _sym )
+#define CONFIG_SYMBOL PREFIX_OBJECT ( obj_config_ )
+
+/** Always provide the symbol for the current object (defined by -DOBJECT) */
+PROVIDE_SYMBOL ( OBJECT_SYMBOL );
+
+/** Pull in an object-specific configuration file if available */
+REQUEST_EXPANDED ( CONFIG_SYMBOL );
+
+/** Explicitly require another object */
+#define REQUIRE_OBJECT( _obj ) REQUIRE_SYMBOL ( obj_ ## _obj )
+
+/** Pull in another object if it exists */
+#define REQUEST_OBJECT( _obj ) REQUEST_SYMBOL ( obj_ ## _obj )
+
+/** @} */
+
+/** Select file identifier for errno.h (if used) */
+#define ERRFILE PREFIX_OBJECT ( ERRFILE_ )
+
+#ifndef ASSEMBLY
+
+/** Declare a function as weak (use *before* the definition)
+ *
+ * Due to a bug in at least GCC 4.4.4 and earlier, weak symbols may be
+ * inlined if they have hidden visibility (see above for why hidden
+ * visibility is used). This results in the non-weak symbol never
+ * being used, so explicitly mark the function as noinline to prevent
+ * inlining.
+ */
+#define __weak __attribute__ (( weak, noinline ))
+
+/** Prevent a function from being optimized away without inlining
+ *
+ * Calls to functions with void return type that contain no code in their body
+ * may be removed by gcc's optimizer even when inlining is inhibited. Placing
+ * this macro in the body of the function prevents that from occurring.
+ */
+#define __keepme asm("");
+
+#endif
+
+/** @defgroup dbg Debugging infrastructure
+ * @{
+ */
+
+/** @def DBG
+ *
+ * Print a debugging message.
+ *
+ * The debug level is set at build time by specifying the @c DEBUG=
+ * parameter on the @c make command line. For example, to enable
+ * debugging for the PCI bus functions (in pci.c) in a @c .dsk image
+ * for the @c rtl8139 card, you could use the command line
+ *
+ * @code
+ *
+ * make bin/rtl8139.dsk DEBUG=pci
+ *
+ * @endcode
+ *
+ * This will enable the debugging statements (DBG()) in pci.c. If
+ * debugging is not enabled, DBG() statements will be ignored.
+ *
+ * You can enable debugging in several objects simultaneously by
+ * separating them with commas, as in
+ *
+ * @code
+ *
+ * make bin/rtl8139.dsk DEBUG=pci,buffer,heap
+ *
+ * @endcode
+ *
+ * You can increase the debugging level for an object by specifying it
+ * with @c :N, where @c N is the level, as in
+ *
+ * @code
+ *
+ * make bin/rtl8139.dsk DEBUG=pci,buffer:2,heap
+ *
+ * @endcode
+ *
+ * which would enable debugging for the PCI, buffer-handling and
+ * heap-allocation code, with the buffer-handling code at level 2.
+ *
+ */
+
+#ifndef DBGLVL_MAX
+#define NDEBUG
+#define DBGLVL_MAX 0
+#endif
+
+#ifndef ASSEMBLY
+
+/** printf() for debugging */
+extern void __attribute__ (( format ( printf, 1, 2 ) ))
+dbg_printf ( const char *fmt, ... );
+extern void dbg_autocolourise ( unsigned long id );
+extern void dbg_decolourise ( void );
+extern void dbg_hex_dump_da ( unsigned long dispaddr,
+ const void *data, unsigned long len );
+extern void dbg_md5_da ( unsigned long dispaddr,
+ const void *data, unsigned long len );
+extern void dbg_pause ( void );
+extern void dbg_more ( void );
+
+/* Allow for selective disabling of enabled debug levels */
+#if DBGLVL_MAX
+int __debug_disable;
+#define DBGLVL ( DBGLVL_MAX & ~__debug_disable )
+#define DBG_DISABLE( level ) do { \
+ __debug_disable |= (level); \
+ } while ( 0 )
+#define DBG_ENABLE( level ) do { \
+ __debug_disable &= ~(level); \
+ } while ( 0 )
+#else
+#define DBGLVL 0
+#define DBG_DISABLE( level ) do { } while ( 0 )
+#define DBG_ENABLE( level ) do { } while ( 0 )
+#endif
+
+#define DBGLVL_LOG 1
+#define DBG_LOG ( DBGLVL & DBGLVL_LOG )
+#define DBGLVL_EXTRA 2
+#define DBG_EXTRA ( DBGLVL & DBGLVL_EXTRA )
+#define DBGLVL_PROFILE 4
+#define DBG_PROFILE ( DBGLVL & DBGLVL_PROFILE )
+#define DBGLVL_IO 8
+#define DBG_IO ( DBGLVL & DBGLVL_IO )
+
+/**
+ * Print debugging message if we are at a certain debug level
+ *
+ * @v level Debug level
+ * @v ... printf() argument list
+ */
+#define DBG_IF( level, ... ) do { \
+ if ( DBG_ ## level ) { \
+ dbg_printf ( __VA_ARGS__ ); \
+ } \
+ } while ( 0 )
+
+/**
+ * Print a hex dump if we are at a certain debug level
+ *
+ * @v level Debug level
+ * @v dispaddr Display address
+ * @v data Data to print
+ * @v len Length of data
+ */
+#define DBG_HDA_IF( level, dispaddr, data, len ) do { \
+ if ( DBG_ ## level ) { \
+ union { \
+ unsigned long ul; \
+ typeof ( dispaddr ) raw; \
+ } da; \
+ da.ul = 0; \
+ da.raw = dispaddr; \
+ dbg_hex_dump_da ( da.ul, data, len ); \
+ } \
+ } while ( 0 )
+
+/**
+ * Print a hex dump if we are at a certain debug level
+ *
+ * @v level Debug level
+ * @v data Data to print
+ * @v len Length of data
+ */
+#define DBG_HD_IF( level, data, len ) do { \
+ const void *_data = data; \
+ DBG_HDA_IF ( level, _data, _data, len ); \
+ } while ( 0 )
+
+/**
+ * Print an MD5 checksum if we are at a certain debug level
+ *
+ * @v level Debug level
+ * @v dispaddr Display address
+ * @v data Data to print
+ * @v len Length of data
+ */
+#define DBG_MD5A_IF( level, dispaddr, data, len ) do { \
+ if ( DBG_ ## level ) { \
+ union { \
+ unsigned long ul; \
+ typeof ( dispaddr ) raw; \
+ } da; \
+ da.ul = 0; \
+ da.raw = dispaddr; \
+ dbg_md5_da ( da.ul, data, len ); \
+ } \
+ } while ( 0 )
+
+/**
+ * Print an MD5 checksum if we are at a certain debug level
+ *
+ * @v level Debug level
+ * @v data Data to print
+ * @v len Length of data
+ */
+#define DBG_MD5_IF( level, data, len ) do { \
+ const void *_data = data; \
+ DBG_MD5A_IF ( level, _data, _data, len ); \
+ } while ( 0 )
+
+/**
+ * Prompt for key press if we are at a certain debug level
+ *
+ * @v level Debug level
+ */
+#define DBG_PAUSE_IF( level ) do { \
+ if ( DBG_ ## level ) { \
+ dbg_pause(); \
+ } \
+ } while ( 0 )
+
+/**
+ * Prompt for more output data if we are at a certain debug level
+ *
+ * @v level Debug level
+ */
+#define DBG_MORE_IF( level ) do { \
+ if ( DBG_ ## level ) { \
+ dbg_more(); \
+ } \
+ } while ( 0 )
+
+/**
+ * Select colour for debug messages if we are at a certain debug level
+ *
+ * @v level Debug level
+ * @v id Message stream ID
+ */
+#define DBG_AC_IF( level, id ) do { \
+ if ( DBG_ ## level ) { \
+ union { \
+ unsigned long ul; \
+ typeof ( id ) raw; \
+ } dbg_stream; \
+ dbg_stream.ul = 0; \
+ dbg_stream.raw = id; \
+ dbg_autocolourise ( dbg_stream.ul ); \
+ } \
+ } while ( 0 )
+
+/**
+ * Revert colour for debug messages if we are at a certain debug level
+ *
+ * @v level Debug level
+ */
+#define DBG_DC_IF( level ) do { \
+ if ( DBG_ ## level ) { \
+ dbg_decolourise(); \
+ } \
+ } while ( 0 )
+
+/* Autocolourising versions of the DBGxxx_IF() macros */
+
+#define DBGC_IF( level, id, ... ) do { \
+ DBG_AC_IF ( level, id ); \
+ DBG_IF ( level, __VA_ARGS__ ); \
+ DBG_DC_IF ( level ); \
+ } while ( 0 )
+
+#define DBGC_HDA_IF( level, id, ... ) do { \
+ DBG_AC_IF ( level, id ); \
+ DBG_HDA_IF ( level, __VA_ARGS__ ); \
+ DBG_DC_IF ( level ); \
+ } while ( 0 )
+
+#define DBGC_HD_IF( level, id, ... ) do { \
+ DBG_AC_IF ( level, id ); \
+ DBG_HD_IF ( level, __VA_ARGS__ ); \
+ DBG_DC_IF ( level ); \
+ } while ( 0 )
+
+#define DBGC_MD5A_IF( level, id, ... ) do { \
+ DBG_AC_IF ( level, id ); \
+ DBG_MD5A_IF ( level, __VA_ARGS__ ); \
+ DBG_DC_IF ( level ); \
+ } while ( 0 )
+
+#define DBGC_MD5_IF( level, id, ... ) do { \
+ DBG_AC_IF ( level, id ); \
+ DBG_MD5_IF ( level, __VA_ARGS__ ); \
+ DBG_DC_IF ( level ); \
+ } while ( 0 )
+
+#define DBGC_PAUSE_IF( level, id ) do { \
+ DBG_AC_IF ( level, id ); \
+ DBG_PAUSE_IF ( level ); \
+ DBG_DC_IF ( level ); \
+ } while ( 0 )
+
+#define DBGC_MORE_IF( level, id ) do { \
+ DBG_AC_IF ( level, id ); \
+ DBG_MORE_IF ( level ); \
+ DBG_DC_IF ( level ); \
+ } while ( 0 )
+
+/* Versions of the DBGxxx_IF() macros that imply DBGxxx_IF( LOG, ... )*/
+
+#define DBG( ... ) DBG_IF ( LOG, ##__VA_ARGS__ )
+#define DBG_HDA( ... ) DBG_HDA_IF ( LOG, ##__VA_ARGS__ )
+#define DBG_HD( ... ) DBG_HD_IF ( LOG, ##__VA_ARGS__ )
+#define DBG_MD5A( ... ) DBG_MD5A_IF ( LOG, ##__VA_ARGS__ )
+#define DBG_MD5( ... ) DBG_MD5_IF ( LOG, ##__VA_ARGS__ )
+#define DBG_PAUSE( ... ) DBG_PAUSE_IF ( LOG, ##__VA_ARGS__ )
+#define DBG_MORE( ... ) DBG_MORE_IF ( LOG, ##__VA_ARGS__ )
+#define DBGC( ... ) DBGC_IF ( LOG, ##__VA_ARGS__ )
+#define DBGC_HDA( ... ) DBGC_HDA_IF ( LOG, ##__VA_ARGS__ )
+#define DBGC_HD( ... ) DBGC_HD_IF ( LOG, ##__VA_ARGS__ )
+#define DBGC_MD5A( ... ) DBGC_MD5A_IF ( LOG, ##__VA_ARGS__ )
+#define DBGC_MD5( ... ) DBGC_MD5_IF ( LOG, ##__VA_ARGS__ )
+#define DBGC_PAUSE( ... ) DBGC_PAUSE_IF ( LOG, ##__VA_ARGS__ )
+#define DBGC_MORE( ... ) DBGC_MORE_IF ( LOG, ##__VA_ARGS__ )
+
+/* Versions of the DBGxxx_IF() macros that imply DBGxxx_IF( EXTRA, ... )*/
+
+#define DBG2( ... ) DBG_IF ( EXTRA, ##__VA_ARGS__ )
+#define DBG2_HDA( ... ) DBG_HDA_IF ( EXTRA, ##__VA_ARGS__ )
+#define DBG2_HD( ... ) DBG_HD_IF ( EXTRA, ##__VA_ARGS__ )
+#define DBG2_MD5A( ... ) DBG_MD5A_IF ( EXTRA, ##__VA_ARGS__ )
+#define DBG2_MD5( ... ) DBG_MD5_IF ( EXTRA, ##__VA_ARGS__ )
+#define DBG2_PAUSE( ... ) DBG_PAUSE_IF ( EXTRA, ##__VA_ARGS__ )
+#define DBG2_MORE( ... ) DBG_MORE_IF ( EXTRA, ##__VA_ARGS__ )
+#define DBGC2( ... ) DBGC_IF ( EXTRA, ##__VA_ARGS__ )
+#define DBGC2_HDA( ... ) DBGC_HDA_IF ( EXTRA, ##__VA_ARGS__ )
+#define DBGC2_HD( ... ) DBGC_HD_IF ( EXTRA, ##__VA_ARGS__ )
+#define DBGC2_MD5A( ... ) DBGC_MD5A_IF ( EXTRA, ##__VA_ARGS__ )
+#define DBGC2_MD5( ... ) DBGC_MD5_IF ( EXTRA, ##__VA_ARGS__ )
+#define DBGC2_PAUSE( ... ) DBGC_PAUSE_IF ( EXTRA, ##__VA_ARGS__ )
+#define DBGC2_MORE( ... ) DBGC_MORE_IF ( EXTRA, ##__VA_ARGS__ )
+
+/* Versions of the DBGxxx_IF() macros that imply DBGxxx_IF( PROFILE, ... )*/
+
+#define DBGP( ... ) DBG_IF ( PROFILE, ##__VA_ARGS__ )
+#define DBGP_HDA( ... ) DBG_HDA_IF ( PROFILE, ##__VA_ARGS__ )
+#define DBGP_HD( ... ) DBG_HD_IF ( PROFILE, ##__VA_ARGS__ )
+#define DBGP_MD5A( ... ) DBG_MD5A_IF ( PROFILE, ##__VA_ARGS__ )
+#define DBGP_MD5( ... ) DBG_MD5_IF ( PROFILE, ##__VA_ARGS__ )
+#define DBGP_PAUSE( ... ) DBG_PAUSE_IF ( PROFILE, ##__VA_ARGS__ )
+#define DBGP_MORE( ... ) DBG_MORE_IF ( PROFILE, ##__VA_ARGS__ )
+#define DBGCP( ... ) DBGC_IF ( PROFILE, ##__VA_ARGS__ )
+#define DBGCP_HDA( ... ) DBGC_HDA_IF ( PROFILE, ##__VA_ARGS__ )
+#define DBGCP_HD( ... ) DBGC_HD_IF ( PROFILE, ##__VA_ARGS__ )
+#define DBGCP_MD5A( ... ) DBGC_MD5A_IF ( PROFILE, ##__VA_ARGS__ )
+#define DBGCP_MD5( ... ) DBGC_MD5_IF ( PROFILE, ##__VA_ARGS__ )
+#define DBGCP_PAUSE( ... ) DBGC_PAUSE_IF ( PROFILE, ##__VA_ARGS__ )
+#define DBGCP_MORE( ... ) DBGC_MORE_IF ( PROFILE, ##__VA_ARGS__ )
+
+/* Versions of the DBGxxx_IF() macros that imply DBGxxx_IF( IO, ... )*/
+
+#define DBGIO( ... ) DBG_IF ( IO, ##__VA_ARGS__ )
+#define DBGIO_HDA( ... ) DBG_HDA_IF ( IO, ##__VA_ARGS__ )
+#define DBGIO_HD( ... ) DBG_HD_IF ( IO, ##__VA_ARGS__ )
+#define DBGIO_MD5A( ... ) DBG_MD5A_IF ( IO, ##__VA_ARGS__ )
+#define DBGIO_MD5( ... ) DBG_MD5_IF ( IO, ##__VA_ARGS__ )
+#define DBGIO_PAUSE( ... ) DBG_PAUSE_IF ( IO, ##__VA_ARGS__ )
+#define DBGIO_MORE( ... ) DBG_MORE_IF ( IO, ##__VA_ARGS__ )
+#define DBGCIO( ... ) DBGC_IF ( IO, ##__VA_ARGS__ )
+#define DBGCIO_HDA( ... ) DBGC_HDA_IF ( IO, ##__VA_ARGS__ )
+#define DBGCIO_HD( ... ) DBGC_HD_IF ( IO, ##__VA_ARGS__ )
+#define DBGCIO_MD5A( ... ) DBGC_MD5A_IF ( IO, ##__VA_ARGS__ )
+#define DBGCIO_MD5( ... ) DBGC_MD5_IF ( IO, ##__VA_ARGS__ )
+#define DBGCIO_PAUSE( ... ) DBGC_PAUSE_IF ( IO, ##__VA_ARGS__ )
+#define DBGCIO_MORE( ... ) DBGC_MORE_IF ( IO, ##__VA_ARGS__ )
+
+#endif /* ASSEMBLY */
+/** @} */
+
+/** @defgroup attrs Miscellaneous attributes
+ * @{
+ */
+#ifndef ASSEMBLY
+
+/** Declare a variable or data structure as unused. */
+#define __unused __attribute__ (( unused ))
+
+/**
+ * Declare a function as pure - i.e. without side effects
+ */
+#define __pure __attribute__ (( pure ))
+
+/**
+ * Declare a function as const - i.e. it does not access global memory
+ * (including dereferencing pointers passed to it) at all.
+ * Must also not call any non-const functions.
+ */
+#define __const __attribute__ (( const ))
+
+/**
+ * Declare a function's pointer parameters as non-null - i.e. force
+ * compiler to check pointers at compile time and enable possible
+ * optimizations based on that fact
+ */
+#define __nonnull __attribute__ (( nonnull ))
+
+/**
+ * Declare a pointer returned by a function as a unique memory address
+ * as returned by malloc-type functions.
+ */
+#define __malloc __attribute__ (( malloc ))
+
+/**
+ * Declare a function as used.
+ *
+ * Necessary only if the function is called only from assembler code.
+ */
+#define __used __attribute__ (( used ))
+
+/** Declare a data structure to be aligned with 16-byte alignment */
+#define __aligned __attribute__ (( aligned ( 16 ) ))
+
+/** Declare a function to be always inline */
+#define __always_inline __attribute__ (( always_inline ))
+
+/* Force all inline functions to not be instrumented
+ *
+ * This is required to cope with what seems to be a long-standing gcc
+ * bug, in which -finstrument-functions will cause instances of
+ * inlined functions to be reported as further calls to the
+ * *containing* function. This makes instrumentation very difficult
+ * to use.
+ *
+ * Work around this problem by adding the no_instrument_function
+ * attribute to all inlined functions.
+ */
+#define inline inline __attribute__ (( no_instrument_function ))
+
+/**
+ * Shared data.
+ *
+ * To save space in the binary when multiple-driver images are
+ * compiled, uninitialised data areas can be shared between drivers.
+ * This will typically be used to share statically-allocated receive
+ * and transmit buffers between drivers.
+ *
+ * Use as e.g.
+ *
+ * @code
+ *
+ * struct {
+ * char rx_buf[NUM_RX_BUF][RX_BUF_SIZE];
+ * char tx_buf[TX_BUF_SIZE];
+ * } my_static_data __shared;
+ *
+ * @endcode
+ *
+ */
+#define __shared __asm__ ( "_shared_bss" ) __aligned
+
+#endif /* ASSEMBLY */
+/** @} */
+
+/**
+ * Optimisation barrier
+ */
+#ifndef ASSEMBLY
+#define barrier() __asm__ __volatile__ ( "" : : : "memory" )
+#endif /* ASSEMBLY */
+
+/**
+ * @defgroup licences Licence declarations
+ *
+ * For reasons that are partly historical, various different files
+ * within the iPXE codebase have differing licences.
+ *
+ * @{
+ */
+
+/** Declare a file as being in the public domain
+ *
+ * This licence declaration is applicable when a file states itself to
+ * be in the public domain.
+ */
+#define FILE_LICENCE_PUBLIC_DOMAIN \
+ PROVIDE_SYMBOL ( PREFIX_OBJECT ( __licence__public_domain__ ) )
+
+/** Declare a file as being under version 2 (or later) of the GNU GPL
+ *
+ * This licence declaration is applicable when a file states itself to
+ * be licensed under the GNU GPL; "either version 2 of the License, or
+ * (at your option) any later version".
+ */
+#define FILE_LICENCE_GPL2_OR_LATER \
+ PROVIDE_SYMBOL ( PREFIX_OBJECT ( __licence__gpl2_or_later__ ) )
+
+/** Declare a file as being under version 2 of the GNU GPL
+ *
+ * This licence declaration is applicable when a file states itself to
+ * be licensed under version 2 of the GPL, and does not include the
+ * "or, at your option, any later version" clause.
+ */
+#define FILE_LICENCE_GPL2_ONLY \
+ PROVIDE_SYMBOL ( PREFIX_OBJECT ( __licence__gpl2_only__ ) )
+
+/** Declare a file as being under any version of the GNU GPL
+ *
+ * This licence declaration is applicable when a file states itself to
+ * be licensed under the GPL, but does not specify a version.
+ *
+ * According to section 9 of the GPLv2, "If the Program does not
+ * specify a version number of this License, you may choose any
+ * version ever published by the Free Software Foundation".
+ */
+#define FILE_LICENCE_GPL_ANY \
+ PROVIDE_SYMBOL ( PREFIX_OBJECT ( __licence__gpl_any__ ) )
+
+/** Declare a file as being under the three-clause BSD licence
+ *
+ * This licence declaration is applicable when a file states itself to
+ * be licensed under terms allowing redistribution in source and
+ * binary forms (with or without modification) provided that:
+ *
+ * redistributions of source code retain the copyright notice,
+ * list of conditions and any attached disclaimers
+ *
+ * redistributions in binary form reproduce the copyright notice,
+ * list of conditions and any attached disclaimers in the
+ * documentation and/or other materials provided with the
+ * distribution
+ *
+ * the name of the author is not used to endorse or promote
+ * products derived from the software without specific prior
+ * written permission
+ *
+ * It is not necessary for the file to explicitly state that it is
+ * under a "BSD" licence; only that the licensing terms be
+ * functionally equivalent to the standard three-clause BSD licence.
+ */
+#define FILE_LICENCE_BSD3 \
+ PROVIDE_SYMBOL ( PREFIX_OBJECT ( __licence__bsd3__ ) )
+
+/** Declare a file as being under the two-clause BSD licence
+ *
+ * This licence declaration is applicable when a file states itself to
+ * be licensed under terms allowing redistribution in source and
+ * binary forms (with or without modification) provided that:
+ *
+ * redistributions of source code retain the copyright notice,
+ * list of conditions and any attached disclaimers
+ *
+ * redistributions in binary form reproduce the copyright notice,
+ * list of conditions and any attached disclaimers in the
+ * documentation and/or other materials provided with the
+ * distribution
+ *
+ * It is not necessary for the file to explicitly state that it is
+ * under a "BSD" licence; only that the licensing terms be
+ * functionally equivalent to the standard two-clause BSD licence.
+ */
+#define FILE_LICENCE_BSD2 \
+ PROVIDE_SYMBOL ( PREFIX_OBJECT ( __licence__bsd2__ ) )
+
+/** Declare a file as being under the one-clause MIT-style licence
+ *
+ * This licence declaration is applicable when a file states itself to
+ * be licensed under terms allowing redistribution for any purpose
+ * with or without fee, provided that the copyright notice and
+ * permission notice appear in all copies.
+ */
+#define FILE_LICENCE_MIT \
+ PROVIDE_SYMBOL ( PREFIX_OBJECT ( __licence__mit__ ) )
+
+/** Declare a particular licence as applying to a file */
+#define FILE_LICENCE( _licence ) FILE_LICENCE_ ## _licence
+
+/** @} */
+
+/* This file itself is under GPLv2-or-later */
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <bits/compiler.h>
+
+#endif /* COMPILER_H */