Misc helpers

Macros
#define	BKPT()
	Debug controlled breakpoint, only set if DEBUG=1.
#define	ARG_NOT_USED(arg)   ((void)(arg))
	Signifies an argument is not used.

Compiler and Linker Macros
#define	DO_PRAGMA(x)   _Pragma (#x)
	Wrapper for pragmas.
#define	WARNING_SAVE()   DO_PRAGMA(GCC diagnostic push)
	Push the current diagnostic state.
#define	WARNING_DISABLE(warn)   DO_PRAGMA(GCC diagnostic ignored "-W" warn)
	Disable a warning.
#define	WARNING_RESTORE()   DO_PRAGMA(GCC diagnostic pop)
	Restore the diagnostic state from the last WARNING_SAVE().
#define	ATTRIBUTE(x)   __attribute__ (( x ))
	Wraps around a GCC attribute.
#define	ALIGN(bytes)   ATTRIBUTE(aligned (bytes))
	Specifies an alignment attribute.
#define	OPTIMIZE_O0   ATTRIBUTE(optimize("O0"))
	Function optimization disabled.
#define	OPTIMIZE_O1   ATTRIBUTE(optimize("O1"))
	Function optimization level 1.
#define	OPTIMIZE_O2   ATTRIBUTE(optimize("O2"))
	Function optimization level 2.
#define	OPTIMIZE_O3   ATTRIBUTE(optimize("O3"))
	Function optimization level 3.
#define	OPTIMIZE_OG   ATTRIBUTE(optimize("Og"))
	Function optimization for debug.
#define	OPTIMIZE_OS   ATTRIBUTE(optimize("Os"))
	Function optimization for size.
#define	OPTIMIZE_OFAST   ATTRIBUTE(optimize("Ofast"))
	Function optimization for speed.

Bit-flag macros
#define	FLAG(i)   ( 1 << i)
	Create a generic int flag.
#define	FLAG8(i)   ( UINT8_C(1) << i)
	Create an uint8 flag.
#define	FLAG16(i)   (UINT16_C(1) << i)
	Create an uint16 flag.
#define	FLAG32(i)   (UINT32_C(1) << i)
	Create an uint32 flag.
#define	FLAG64(i)   (UINT64_C(1) << i)
	Create an uint64 flag.

Simple Math Macros
#define	max(a, b)   ((a) > (b) ? (a) : (b))
	Selects the maximum between two values.
#define	min(a, b)   ((a) <= (b) ? (a) : (b))
	Selects the minimum between two values.
#define	sign(a)   ((a) >= 0 ? 1 : -1)
	Gets the sign of a value, zero is considered positive.

Detailed Description