zfs/include/os/freebsd/spl/sys/isa_defs.h

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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or https://opensource.org/licenses/CDDL-1.0.
* See the License for the specific language governing permissions
* and limitations under the License.
*
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#ifndef _SYS_ISA_DEFS_H
#define _SYS_ISA_DEFS_H
#include <sys/endian.h>
/*
* This header file serves to group a set of well known defines and to
* set these for each instruction set architecture. These defines may
* be divided into two groups; characteristics of the processor and
* implementation choices for Solaris on a processor.
*
* Processor Characteristics:
*
* _LITTLE_ENDIAN / _BIG_ENDIAN:
* The natural byte order of the processor. A pointer to an int points
* to the least/most significant byte of that int.
*
* _STACK_GROWS_UPWARD / _STACK_GROWS_DOWNWARD:
* The processor specific direction of stack growth. A push onto the
* stack increases/decreases the stack pointer, so it stores data at
* successively higher/lower addresses. (Stackless machines ignored
* without regrets).
*
* _LONG_LONG_HTOL / _LONG_LONG_LTOH:
* A pointer to a long long points to the most/least significant long
* within that long long.
*
* _BIT_FIELDS_HTOL / _BIT_FIELDS_LTOH:
* The C compiler assigns bit fields from the high/low to the low/high end
* of an int (most to least significant vs. least to most significant).
*
* _IEEE_754:
* The processor (or supported implementations of the processor)
* supports the ieee-754 floating point standard. No other floating
* point standards are supported (or significant). Any other supported
* floating point formats are expected to be cased on the ISA processor
* symbol.
*
* _CHAR_IS_UNSIGNED / _CHAR_IS_SIGNED:
* The C Compiler implements objects of type `char' as `unsigned' or
* `signed' respectively. This is really an implementation choice of
* the compiler writer, but it is specified in the ABI and tends to
* be uniform across compilers for an instruction set architecture.
* Hence, it has the properties of a processor characteristic.
*
* _CHAR_ALIGNMENT / _SHORT_ALIGNMENT / _INT_ALIGNMENT / _LONG_ALIGNMENT /
* _LONG_LONG_ALIGNMENT / _DOUBLE_ALIGNMENT / _LONG_DOUBLE_ALIGNMENT /
* _POINTER_ALIGNMENT / _FLOAT_ALIGNMENT:
* The ABI defines alignment requirements of each of the primitive
* object types. Some, if not all, may be hardware requirements as
* well. The values are expressed in "byte-alignment" units.
*
* _MAX_ALIGNMENT:
* The most stringent alignment requirement as specified by the ABI.
* Equal to the maximum of all the above _XXX_ALIGNMENT values.
*
* _ALIGNMENT_REQUIRED:
* True or false (1 or 0) whether or not the hardware requires the ABI
* alignment.
*
* _LONG_LONG_ALIGNMENT_32
* The 32-bit ABI supported by a 64-bit kernel may have different
* alignment requirements for primitive object types. The value of this
* identifier is expressed in "byte-alignment" units.
*
* _HAVE_CPUID_INSN
* This indicates that the architecture supports the 'cpuid'
* instruction as defined by Intel. (Intel allows other vendors
* to extend the instruction for their own purposes.)
*
*
* Implementation Choices:
*
* _ILP32 / _LP64:
* This specifies the compiler data type implementation as specified in
* the relevant ABI. The choice between these is strongly influenced
* by the underlying hardware, but is not absolutely tied to it.
* Currently only two data type models are supported:
*
* _ILP32:
* Int/Long/Pointer are 32 bits. This is the historical UNIX
* and Solaris implementation. Due to its historical standing,
* this is the default case.
*
* _LP64:
* Long/Pointer are 64 bits, Int is 32 bits. This is the chosen
* implementation for 64-bit ABIs such as SPARC V9.
*
* _I32LPx:
* A compilation environment where 'int' is 32-bit, and
* longs and pointers are simply the same size.
*
* In all cases, Char is 8 bits and Short is 16 bits.
*
* _SUNOS_VTOC_8 / _SUNOS_VTOC_16 / _SVR4_VTOC_16:
* This specifies the form of the disk VTOC (or label):
*
* _SUNOS_VTOC_8:
* This is a VTOC form which is upwardly compatible with the
* SunOS 4.x disk label and allows 8 partitions per disk.
*
* _SUNOS_VTOC_16:
* In this format the incore vtoc image matches the ondisk
* version. It allows 16 slices per disk, and is not
* compatible with the SunOS 4.x disk label.
*
* Note that these are not the only two VTOC forms possible and
* additional forms may be added. One possible form would be the
* SVr4 VTOC form. The symbol for that is reserved now, although
* it is not implemented.
*
* _SVR4_VTOC_16:
* This VTOC form is compatible with the System V Release 4
* VTOC (as implemented on the SVr4 Intel and 3b ports) with
* 16 partitions per disk.
*
*
* _DMA_USES_PHYSADDR / _DMA_USES_VIRTADDR
* This describes the type of addresses used by system DMA:
*
* _DMA_USES_PHYSADDR:
* This type of DMA, used in the x86 implementation,
* requires physical addresses for DMA buffers. The 24-bit
* addresses used by some legacy boards is the source of the
* "low-memory" (<16MB) requirement for some devices using DMA.
*
* _DMA_USES_VIRTADDR:
* This method of DMA allows the use of virtual addresses for
* DMA transfers.
*
* _FIRMWARE_NEEDS_FDISK / _NO_FDISK_PRESENT
* This indicates the presence/absence of an fdisk table.
*
* _FIRMWARE_NEEDS_FDISK
* The fdisk table is required by system firmware. If present,
* it allows a disk to be subdivided into multiple fdisk
* partitions, each of which is equivalent to a separate,
* virtual disk. This enables the co-existence of multiple
* operating systems on a shared hard disk.
*
* _NO_FDISK_PRESENT
* If the fdisk table is absent, it is assumed that the entire
* media is allocated for a single operating system.
*
* _HAVE_TEM_FIRMWARE
* Defined if this architecture has the (fallback) option of
* using prom_* calls for doing I/O if a suitable kernel driver
* is not available to do it.
*
* _DONT_USE_1275_GENERIC_NAMES
* Controls whether or not device tree node names should
* comply with the IEEE 1275 "Generic Names" Recommended
* Practice. With _DONT_USE_GENERIC_NAMES, device-specific
* names identifying the particular device will be used.
*
* __i386_COMPAT
* This indicates whether the i386 ABI is supported as a *non-native*
* mode for the platform. When this symbol is defined:
* - 32-bit xstat-style system calls are enabled
* - 32-bit xmknod-style system calls are enabled
* - 32-bit system calls use i386 sizes -and- alignments
*
* Note that this is NOT defined for the i386 native environment!
*
* __x86
* This is ONLY a synonym for defined(__i386) || defined(__amd64)
* which is useful only insofar as these two architectures share
* common attributes. Analogous to __sparc.
*
* _PSM_MODULES
* This indicates whether or not the implementation uses PSM
* modules for processor support, reading /etc/mach from inside
* the kernel to extract a list.
*
* _RTC_CONFIG
* This indicates whether or not the implementation uses /etc/rtc_config
* to configure the real-time clock in the kernel.
*
* _UNIX_KRTLD
* This indicates that the implementation uses a dynamically
* linked unix + krtld to form the core kernel image at boot
* time, or (in the absence of this symbol) a prelinked kernel image.
*
* _OBP
* This indicates the firmware interface is OBP.
*
* _SOFT_HOSTID
* This indicates that the implementation obtains the hostid
* from the file /etc/hostid, rather than from hardware.
*/
#ifdef __cplusplus
extern "C" {
#endif
/*
* The following set of definitions characterize Solaris on AMD's
* 64-bit systems.
*/
#if defined(__x86_64) || defined(__amd64)
#if !defined(__amd64)
#define __amd64 /* preferred guard */
#endif
#if !defined(__x86)
#define __x86
#endif
/*
* Define the appropriate "processor characteristics"
*/
#define _STACK_GROWS_DOWNWARD
#define _LONG_LONG_LTOH
#define _BIT_FIELDS_LTOH
#define _IEEE_754
#define _CHAR_IS_SIGNED
#define _BOOL_ALIGNMENT 1
#define _CHAR_ALIGNMENT 1
#define _SHORT_ALIGNMENT 2
#define _INT_ALIGNMENT 4
#define _FLOAT_ALIGNMENT 4
#define _FLOAT_COMPLEX_ALIGNMENT 4
#define _LONG_ALIGNMENT 8
#define _LONG_LONG_ALIGNMENT 8
#define _DOUBLE_ALIGNMENT 8
#define _DOUBLE_COMPLEX_ALIGNMENT 8
#define _LONG_DOUBLE_ALIGNMENT 16
#define _LONG_DOUBLE_COMPLEX_ALIGNMENT 16
#define _POINTER_ALIGNMENT 8
#define _MAX_ALIGNMENT 16
#define _ALIGNMENT_REQUIRED 1
/*
* Different alignment constraints for the i386 ABI in compatibility mode
*/
#define _LONG_LONG_ALIGNMENT_32 4
/*
* Define the appropriate "implementation choices".
*/
#if !defined(_LP64)
#error "_LP64 not defined"
#endif
#if !defined(_I32LPx)
#define _I32LPx
#endif
#define _MULTI_DATAMODEL
#define _SUNOS_VTOC_16
#define _DMA_USES_PHYSADDR
#define _FIRMWARE_NEEDS_FDISK
#define __i386_COMPAT
#define _PSM_MODULES
#define _RTC_CONFIG
#define _SOFT_HOSTID
#define _DONT_USE_1275_GENERIC_NAMES
#define _HAVE_CPUID_INSN
/*
* The feature test macro __i386 is generic for all processors implementing
* the Intel 386 instruction set or a superset of it. Specifically, this
* includes all members of the 386, 486, and Pentium family of processors.
*/
#elif defined(__i386) || defined(__i386__)
#if !defined(__i386)
#define __i386
#endif
#if !defined(__x86)
#define __x86
#endif
/*
* Define the appropriate "processor characteristics"
*/
#define _STACK_GROWS_DOWNWARD
#define _LONG_LONG_LTOH
#define _BIT_FIELDS_LTOH
#define _IEEE_754
#define _CHAR_IS_SIGNED
#define _BOOL_ALIGNMENT 1
#define _CHAR_ALIGNMENT 1
#define _SHORT_ALIGNMENT 2
#define _INT_ALIGNMENT 4
#define _FLOAT_ALIGNMENT 4
#define _FLOAT_COMPLEX_ALIGNMENT 4
#define _LONG_ALIGNMENT 4
#define _LONG_LONG_ALIGNMENT 4
#define _DOUBLE_ALIGNMENT 4
#define _DOUBLE_COMPLEX_ALIGNMENT 4
#define _LONG_DOUBLE_ALIGNMENT 4
#define _LONG_DOUBLE_COMPLEX_ALIGNMENT 4
#define _POINTER_ALIGNMENT 4
#define _MAX_ALIGNMENT 4
#define _ALIGNMENT_REQUIRED 0
#define _LONG_LONG_ALIGNMENT_32 _LONG_LONG_ALIGNMENT
/*
* Define the appropriate "implementation choices".
*/
#if !defined(_ILP32)
#define _ILP32
#endif
#if !defined(_I32LPx)
#define _I32LPx
#endif
#define _SUNOS_VTOC_16
#define _DMA_USES_PHYSADDR
#define _FIRMWARE_NEEDS_FDISK
#define _PSM_MODULES
#define _RTC_CONFIG
#define _SOFT_HOSTID
#define _DONT_USE_1275_GENERIC_NAMES
#define _HAVE_CPUID_INSN
#elif defined(__aarch64__)
/*
* Define the appropriate "processor characteristics"
*/
#define _STACK_GROWS_DOWNWARD
#define _LONG_LONG_LTOH
#define _BIT_FIELDS_LTOH
#define _IEEE_754
#define _CHAR_IS_UNSIGNED
#define _BOOL_ALIGNMENT 1
#define _CHAR_ALIGNMENT 1
#define _SHORT_ALIGNMENT 2
#define _INT_ALIGNMENT 4
#define _FLOAT_ALIGNMENT 4
#define _FLOAT_COMPLEX_ALIGNMENT 4
#define _LONG_ALIGNMENT 8
#define _LONG_LONG_ALIGNMENT 8
#define _DOUBLE_ALIGNMENT 8
#define _DOUBLE_COMPLEX_ALIGNMENT 8
#define _LONG_DOUBLE_ALIGNMENT 16
#define _LONG_DOUBLE_COMPLEX_ALIGNMENT 16
#define _POINTER_ALIGNMENT 8
#define _MAX_ALIGNMENT 16
#define _ALIGNMENT_REQUIRED 1
#define _LONG_LONG_ALIGNMENT_32 _LONG_LONG_ALIGNMENT
/*
* Define the appropriate "implementation choices"
*/
#if !defined(_LP64)
#error "_LP64 not defined"
#endif
#define _SUNOS_VTOC_16
#define _DMA_USES_PHYSADDR
#define _FIRMWARE_NEEDS_FDISK
#define _PSM_MODULES
#define _RTC_CONFIG
#define _DONT_USE_1275_GENERIC_NAMES
#define _HAVE_CPUID_INSN
#elif defined(__riscv)
/*
* Define the appropriate "processor characteristics"
*/
#define _STACK_GROWS_DOWNWARD
#define _LONG_LONG_LTOH
#define _BIT_FIELDS_LTOH
#define _IEEE_754
#define _CHAR_IS_UNSIGNED
#define _BOOL_ALIGNMENT 1
#define _CHAR_ALIGNMENT 1
#define _SHORT_ALIGNMENT 2
#define _INT_ALIGNMENT 4
#define _FLOAT_ALIGNMENT 4
#define _FLOAT_COMPLEX_ALIGNMENT 4
#define _LONG_ALIGNMENT 8
#define _LONG_LONG_ALIGNMENT 8
#define _DOUBLE_ALIGNMENT 8
#define _DOUBLE_COMPLEX_ALIGNMENT 8
#define _LONG_DOUBLE_ALIGNMENT 16
#define _LONG_DOUBLE_COMPLEX_ALIGNMENT 16
#define _POINTER_ALIGNMENT 8
#define _MAX_ALIGNMENT 16
#define _ALIGNMENT_REQUIRED 1
#define _LONG_LONG_ALIGNMENT_32 _LONG_LONG_ALIGNMENT
/*
* Define the appropriate "implementation choices"
*/
#if !defined(_LP64)
#define _LP64
#endif
#define _SUNOS_VTOC_16
#define _DMA_USES_PHYSADDR
#define _FIRMWARE_NEEDS_FDISK
#define _PSM_MODULES
#define _RTC_CONFIG
#define _DONT_USE_1275_GENERIC_NAMES
#define _HAVE_CPUID_INSN
#elif defined(__arm__)
/*
* Define the appropriate "processor characteristics"
*/
#define _STACK_GROWS_DOWNWARD
#define _LONG_LONG_LTOH
#define _BIT_FIELDS_LTOH
#define _IEEE_754
#define _CHAR_IS_SIGNED
#define _BOOL_ALIGNMENT 1
#define _CHAR_ALIGNMENT 1
#define _SHORT_ALIGNMENT 2
#define _INT_ALIGNMENT 4
#define _FLOAT_ALIGNMENT 4
#define _FLOAT_COMPLEX_ALIGNMENT 4
#define _LONG_ALIGNMENT 4
#define _LONG_LONG_ALIGNMENT 4
#define _DOUBLE_ALIGNMENT 4
#define _DOUBLE_COMPLEX_ALIGNMENT 4
#define _LONG_DOUBLE_ALIGNMENT 4
#define _LONG_DOUBLE_COMPLEX_ALIGNMENT 4
#define _POINTER_ALIGNMENT 4
#define _MAX_ALIGNMENT 4
#define _ALIGNMENT_REQUIRED 0
#define _LONG_LONG_ALIGNMENT_32 _LONG_LONG_ALIGNMENT
/*
* Define the appropriate "implementation choices".
*/
#if !defined(_ILP32)
#define _ILP32
#endif
#if !defined(_I32LPx)
#define _I32LPx
#endif
#define _SUNOS_VTOC_16
#define _DMA_USES_PHYSADDR
#define _FIRMWARE_NEEDS_FDISK
#define _PSM_MODULES
#define _RTC_CONFIG
#define _DONT_USE_1275_GENERIC_NAMES
#define _HAVE_CPUID_INSN
#elif defined(__mips__)
/*
* Define the appropriate "processor characteristics"
*/
#define _STACK_GROWS_DOWNWARD
#define _LONG_LONG_LTOH
#define _BIT_FIELDS_LTOH
#define _IEEE_754
#define _CHAR_IS_SIGNED
#define _BOOL_ALIGNMENT 1
#define _CHAR_ALIGNMENT 1
#define _SHORT_ALIGNMENT 2
#define _INT_ALIGNMENT 4
#define _FLOAT_ALIGNMENT 4
#define _FLOAT_COMPLEX_ALIGNMENT 4
#if defined(__mips_n64)
#define _LONG_ALIGNMENT 8
#define _LONG_LONG_ALIGNMENT 8
#define _DOUBLE_ALIGNMENT 8
#define _DOUBLE_COMPLEX_ALIGNMENT 8
#define _LONG_DOUBLE_ALIGNMENT 8
#define _LONG_DOUBLE_COMPLEX_ALIGNMENT 8
#define _POINTER_ALIGNMENT 8
#define _MAX_ALIGNMENT 8
#define _ALIGNMENT_REQUIRED 0
#define _LONG_LONG_ALIGNMENT_32 _INT_ALIGNMENT
/*
* Define the appropriate "implementation choices".
*/
#if !defined(_LP64)
#error "_LP64 not defined"
#endif
#else
#define _LONG_ALIGNMENT 4
#define _LONG_LONG_ALIGNMENT 4
#define _DOUBLE_ALIGNMENT 4
#define _DOUBLE_COMPLEX_ALIGNMENT 4
#define _LONG_DOUBLE_ALIGNMENT 4
#define _LONG_DOUBLE_COMPLEX_ALIGNMENT 4
#define _POINTER_ALIGNMENT 4
#define _MAX_ALIGNMENT 4
#define _ALIGNMENT_REQUIRED 0
#define _LONG_LONG_ALIGNMENT_32 _LONG_LONG_ALIGNMENT
/*
* Define the appropriate "implementation choices".
*/
#if !defined(_ILP32)
#define _ILP32
#endif
#if !defined(_I32LPx)
#define _I32LPx
#endif
#endif
#define _SUNOS_VTOC_16
#define _DMA_USES_PHYSADDR
#define _FIRMWARE_NEEDS_FDISK
#define _PSM_MODULES
#define _RTC_CONFIG
#define _DONT_USE_1275_GENERIC_NAMES
#define _HAVE_CPUID_INSN
#elif defined(__powerpc__)
#if defined(__BIG_ENDIAN__)
#define _BIT_FIELDS_HTOL
#else
#define _BIT_FIELDS_LTOH
#endif
#if !defined(__powerpc)
#define __powerpc
#endif
#if defined(__powerpc64__)
#define _LONG_LONG_ALIGNMENT 8
#define _MULTI_DATAMODEL
#else
#define _LONG_LONG_ALIGNMENT 4
#endif
#define _LONG_LONG_ALIGNMENT_32 4
#define _ALIGNMENT_REQUIRED 1
#define _SUNOS_VTOC_16 1
/*
* The following set of definitions characterize the Solaris on SPARC systems.
*
* The symbol __sparc indicates any of the SPARC family of processor
* architectures. This includes SPARC V7, SPARC V8 and SPARC V9.
*
* The symbol __sparcv8 indicates the 32-bit SPARC V8 architecture as defined
* by Version 8 of the SPARC Architecture Manual. (SPARC V7 is close enough
* to SPARC V8 for the former to be subsumed into the latter definition.)
*
* The symbol __sparcv9 indicates the 64-bit SPARC V9 architecture as defined
* by Version 9 of the SPARC Architecture Manual.
*
* The symbols __sparcv8 and __sparcv9 are mutually exclusive, and are only
* relevant when the symbol __sparc is defined.
*/
/*
* XXX Due to the existence of 5110166, "defined(__sparcv9)" needs to be added
* to support backwards builds. This workaround should be removed in s10_71.
*/
#elif defined(__sparc) || defined(__sparcv9) || defined(__sparc__)
#if !defined(__sparc)
#define __sparc
#endif
/*
* You can be 32-bit or 64-bit, but not both at the same time.
*/
#if defined(__sparcv8) && defined(__sparcv9)
#error "SPARC Versions 8 and 9 are mutually exclusive choices"
#endif
/*
* Existing compilers do not set __sparcv8. Years will transpire before
* the compilers can be depended on to set the feature test macro. In
* the interim, we'll set it here on the basis of historical behaviour;
* if you haven't asked for SPARC V9, then you must've meant SPARC V8.
*/
#if !defined(__sparcv9) && !defined(__sparcv8)
#define __sparcv8
#endif
/*
* Define the appropriate "processor characteristics" shared between
* all Solaris on SPARC systems.
*/
#define _STACK_GROWS_DOWNWARD
#define _LONG_LONG_HTOL
#define _BIT_FIELDS_HTOL
#define _IEEE_754
#define _CHAR_IS_SIGNED
#define _BOOL_ALIGNMENT 1
#define _CHAR_ALIGNMENT 1
#define _SHORT_ALIGNMENT 2
#define _INT_ALIGNMENT 4
#define _FLOAT_ALIGNMENT 4
#define _FLOAT_COMPLEX_ALIGNMENT 4
#define _LONG_LONG_ALIGNMENT 8
#define _DOUBLE_ALIGNMENT 8
#define _DOUBLE_COMPLEX_ALIGNMENT 8
#define _ALIGNMENT_REQUIRED 1
/*
* Define the appropriate "implementation choices" shared between versions.
*/
#define _SUNOS_VTOC_8
#define _DMA_USES_VIRTADDR
#define _NO_FDISK_PRESENT
#define _HAVE_TEM_FIRMWARE
#define _OBP
/*
* The following set of definitions characterize the implementation of
* 32-bit Solaris on SPARC V8 systems.
*/
#if defined(__sparcv8)
/*
* Define the appropriate "processor characteristics"
*/
#define _LONG_ALIGNMENT 4
#define _LONG_DOUBLE_ALIGNMENT 8
#define _LONG_DOUBLE_COMPLEX_ALIGNMENT 8
#define _POINTER_ALIGNMENT 4
#define _MAX_ALIGNMENT 8
#define _LONG_LONG_ALIGNMENT_32 _LONG_LONG_ALIGNMENT
/*
* Define the appropriate "implementation choices"
*/
#define _ILP32
#if !defined(_I32LPx)
#define _I32LPx
#endif
/*
* The following set of definitions characterize the implementation of
* 64-bit Solaris on SPARC V9 systems.
*/
#elif defined(__sparcv9)
/*
* Define the appropriate "processor characteristics"
*/
#define _LONG_ALIGNMENT 8
#define _LONG_DOUBLE_ALIGNMENT 16
#define _LONG_DOUBLE_COMPLEX_ALIGNMENT 16
#define _POINTER_ALIGNMENT 8
#define _MAX_ALIGNMENT 16
#define _LONG_LONG_ALIGNMENT_32 _LONG_LONG_ALIGNMENT
/*
* Define the appropriate "implementation choices"
*/
#if !defined(_LP64)
#error "_LP64 not defined"
#endif
#if !defined(_I32LPx)
#define _I32LPx
#endif
#define _MULTI_DATAMODEL
#else
#error "unknown SPARC version"
#endif
/*
* #error is strictly ansi-C, but works as well as anything for K&R systems.
*/
#else
#error "ISA not supported"
#endif
#if defined(_ILP32) && defined(_LP64)
#error "Both _ILP32 and _LP64 are defined"
#endif
#if BYTE_ORDER == _BIG_ENDIAN
#define _ZFS_BIG_ENDIAN
#elif BYTE_ORDER == _LITTLE_ENDIAN
#define _ZFS_LITTLE_ENDIAN
#else
#error "unknown byte order"
#endif
#ifdef __cplusplus
}
#endif
#endif /* _SYS_ISA_DEFS_H */