path: root/gcc/config/rs6000/altivec.h

/* PowerPC AltiVec include file.
   Copyright (C) 2002, 2003, 2004, 2005, 2008 Free Software Foundation, Inc.
   Contributed by Aldy Hernandez (aldyh@redhat.com).
   Rewritten by Paolo Bonzini (bonzini@gnu.org).

   This file is part of GCC.

   GCC is free software; you can redistribute it and/or modify it
   under the terms of the GNU General Public License as published
   by the Free Software Foundation; either version 2, or (at your
   option) any later version.

   GCC is distributed in the hope that it will be useful, but WITHOUT
   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
   or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
   License for more details.

   You should have received a copy of the GNU General Public License
   along with GCC; see the file COPYING.  If not, write to the
   Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston,
   MA 02110-1301, USA.  */

/* As a special exception, if you include this header file into source
   files compiled by GCC, this header file does not by itself cause
   the resulting executable to be covered by the GNU General Public
   License.  This exception does not however invalidate any other
   reasons why the executable file might be covered by the GNU General
   Public License.  */

/* Implemented to conform to the specification included in the AltiVec
   Technology Programming Interface Manual (ALTIVECPIM/D 6/1999 Rev 0).  */

#ifndef _ALTIVEC_H
#define _ALTIVEC_H 1

#if !defined(__VEC__) || !defined(__ALTIVEC__)
#error Use the "-maltivec" flag to enable PowerPC AltiVec support
#endif

/* If __APPLE_ALTIVEC__ is defined, the compiler supports 'vector',
   'pixel' and 'bool' as context-sensitive AltiVec keywords (in 
   non-AltiVec contexts, they revert to their original meanings,
   if any), so we do not need to define them as macros.  */

#if !defined(__APPLE_ALTIVEC__)
/* You are allowed to undef these for C++ compatibility.  */
#define vector __vector
#define pixel __pixel
#define bool __bool
#endif

/* Condition register codes for AltiVec predicates. */

#define __CR6_EQ		0
#define __CR6_EQ_REV		1
#define __CR6_LT		2
#define __CR6_LT_REV		3

/* Synonyms.  */
#define vec_vaddcuw vec_addc
#define vec_vand vec_and
#define vec_vandc vec_andc
#define vec_vrfip vec_ceil
#define vec_vcmpbfp vec_cmpb
#define vec_vcmpgefp vec_cmpge
#define vec_vctsxs vec_cts
#define vec_vctuxs vec_ctu
#define vec_vexptefp vec_expte
#define vec_vrfim vec_floor
#define vec_lvx vec_ld
#define vec_lvxl vec_ldl
#define vec_vlogefp vec_loge
#define vec_vmaddfp vec_madd
#define vec_vmhaddshs vec_madds
#define vec_vmladduhm vec_mladd
#define vec_vmhraddshs vec_mradds
#define vec_vnmsubfp vec_nmsub
#define vec_vnor vec_nor
#define vec_vor vec_or
#define vec_vpkpx vec_packpx
#define vec_vperm vec_perm
#define vec_vrefp vec_re
#define vec_vrfin vec_round
#define vec_vrsqrtefp vec_rsqrte
#define vec_vsel vec_sel
#define vec_vsldoi vec_sld
#define vec_vsl vec_sll
#define vec_vslo vec_slo
#define vec_vspltisb vec_splat_s8
#define vec_vspltish vec_splat_s16
#define vec_vspltisw vec_splat_s32
#define vec_vsr vec_srl
#define vec_vsro vec_sro
#define vec_stvx vec_st
#define vec_stvxl vec_stl
#define vec_vsubcuw vec_subc
#define vec_vsum2sws vec_sum2s
#define vec_vsumsws vec_sums
#define vec_vrfiz vec_trunc
#define vec_vxor vec_xor

/* Functions that are resolved by the backend to one of the
   typed builtins.  */
#define vec_vaddfp __builtin_vec_vaddfp
#define vec_addc __builtin_vec_addc
#define vec_vaddsws __builtin_vec_vaddsws
#define vec_vaddshs __builtin_vec_vaddshs
#define vec_vaddsbs __builtin_vec_vaddsbs
#define vec_vavgsw __builtin_vec_vavgsw
#define vec_vavguw __builtin_vec_vavguw
#define vec_vavgsh __builtin_vec_vavgsh
#define vec_vavguh __builtin_vec_vavguh
#define vec_vavgsb __builtin_vec_vavgsb
#define vec_vavgub __builtin_vec_vavgub
#define vec_ceil __builtin_vec_ceil
#define vec_cmpb __builtin_vec_cmpb
#define vec_vcmpeqfp __builtin_vec_vcmpeqfp
#define vec_cmpge __builtin_vec_cmpge
#define vec_vcmpgtfp __builtin_vec_vcmpgtfp
#define vec_vcmpgtsw __builtin_vec_vcmpgtsw
#define vec_vcmpgtuw __builtin_vec_vcmpgtuw
#define vec_vcmpgtsh __builtin_vec_vcmpgtsh
#define vec_vcmpgtuh __builtin_vec_vcmpgtuh
#define vec_vcmpgtsb __builtin_vec_vcmpgtsb
#define vec_vcmpgtub __builtin_vec_vcmpgtub
#define vec_vcfsx __builtin_vec_vcfsx
#define vec_vcfux __builtin_vec_vcfux
#define vec_cts __builtin_vec_cts
#define vec_ctu __builtin_vec_ctu
#define vec_expte __builtin_vec_expte
#define vec_floor __builtin_vec_floor
#define vec_loge __builtin_vec_loge
#define vec_madd __builtin_vec_madd
#define vec_madds __builtin_vec_madds
#define vec_mtvscr __builtin_vec_mtvscr
#define vec_vmaxfp __builtin_vec_vmaxfp
#define vec_vmaxsw __builtin_vec_vmaxsw
#define vec_vmaxsh __builtin_vec_vmaxsh
#define vec_vmaxsb __builtin_vec_vmaxsb
#define vec_vminfp __builtin_vec_vminfp
#define vec_vminsw __builtin_vec_vminsw
#define vec_vminsh __builtin_vec_vminsh
#define vec_vminsb __builtin_vec_vminsb
#define vec_mradds __builtin_vec_mradds
#define vec_vmsumshm __builtin_vec_vmsumshm
#define vec_vmsumuhm __builtin_vec_vmsumuhm
#define vec_vmsummbm __builtin_vec_vmsummbm
#define vec_vmsumubm __builtin_vec_vmsumubm
#define vec_vmsumshs __builtin_vec_vmsumshs
#define vec_vmsumuhs __builtin_vec_vmsumuhs
#define vec_vmulesb __builtin_vec_vmulesb
#define vec_vmulesh __builtin_vec_vmulesh
#define vec_vmuleuh __builtin_vec_vmuleuh
#define vec_vmuleub __builtin_vec_vmuleub
#define vec_vmulosh __builtin_vec_vmulosh
#define vec_vmulouh __builtin_vec_vmulouh
#define vec_vmulosb __builtin_vec_vmulosb
#define vec_vmuloub __builtin_vec_vmuloub
#define vec_nmsub __builtin_vec_nmsub
#define vec_packpx __builtin_vec_packpx
#define vec_vpkswss __builtin_vec_vpkswss
#define vec_vpkuwus __builtin_vec_vpkuwus
#define vec_vpkshss __builtin_vec_vpkshss
#define vec_vpkuhus __builtin_vec_vpkuhus
#define vec_vpkswus __builtin_vec_vpkswus
#define vec_vpkshus __builtin_vec_vpkshus
#define vec_re __builtin_vec_re
#define vec_round __builtin_vec_round
#define vec_rsqrte __builtin_vec_rsqrte
#define vec_vsubfp __builtin_vec_vsubfp
#define vec_subc __builtin_vec_subc
#define vec_vsubsws __builtin_vec_vsubsws
#define vec_vsubshs __builtin_vec_vsubshs
#define vec_vsubsbs __builtin_vec_vsubsbs
#define vec_sum4s __builtin_vec_sum4s
#define vec_vsum4shs __builtin_vec_vsum4shs
#define vec_vsum4sbs __builtin_vec_vsum4sbs
#define vec_vsum4ubs __builtin_vec_vsum4ubs
#define vec_sum2s __builtin_vec_sum2s
#define vec_sums __builtin_vec_sums
#define vec_trunc __builtin_vec_trunc
#define vec_vupkhpx __builtin_vec_vupkhpx
#define vec_vupkhsh __builtin_vec_vupkhsh
#define vec_vupkhsb __builtin_vec_vupkhsb
#define vec_vupklpx __builtin_vec_vupklpx
#define vec_vupklsh __builtin_vec_vupklsh
#define vec_vupklsb __builtin_vec_vupklsb
#define vec_abs __builtin_vec_abs
#define vec_abss __builtin_vec_abss
#define vec_add __builtin_vec_add
#define vec_adds __builtin_vec_adds
#define vec_and __builtin_vec_and
#define vec_andc __builtin_vec_andc
#define vec_avg __builtin_vec_avg
#define vec_cmpeq __builtin_vec_cmpeq
#define vec_cmpgt __builtin_vec_cmpgt
#define vec_ctf __builtin_vec_ctf
#define vec_dst __builtin_vec_dst
#define vec_dstst __builtin_vec_dstst
#define vec_dststt __builtin_vec_dststt
#define vec_dstt __builtin_vec_dstt
#define vec_ld __builtin_vec_ld
#define vec_lde __builtin_vec_lde
#define vec_ldl __builtin_vec_ldl
#define vec_lvebx __builtin_vec_lvebx
#define vec_lvehx __builtin_vec_lvehx
#define vec_lvewx __builtin_vec_lvewx
/* Cell only intrinsics.  */
#ifdef __PPU__
#define vec_lvlx __builtin_vec_lvlx
#define vec_lvlxl __builtin_vec_lvlxl
#define vec_lvrx __builtin_vec_lvrx
#define vec_lvrxl __builtin_vec_lvrxl
#endif
#define vec_lvsl __builtin_vec_lvsl
#define vec_lvsr __builtin_vec_lvsr
#define vec_max __builtin_vec_max
#define vec_mergeh __builtin_vec_mergeh
#define vec_mergel __builtin_vec_mergel
#define vec_min __builtin_vec_min
#define vec_mladd __builtin_vec_mladd
#define vec_msum __builtin_vec_msum
#define vec_msums __builtin_vec_msums
#define vec_mule __builtin_vec_mule
#define vec_mulo __builtin_vec_mulo
#define vec_nor __builtin_vec_nor
#define vec_or __builtin_vec_or
#define vec_pack __builtin_vec_pack
#define vec_packs __builtin_vec_packs
#define vec_packsu __builtin_vec_packsu
#define vec_perm __builtin_vec_perm
#define vec_rl __builtin_vec_rl
#define vec_sel __builtin_vec_sel
#define vec_sl __builtin_vec_sl
#define vec_sld __builtin_vec_sld
#define vec_sll __builtin_vec_sll
#define vec_slo __builtin_vec_slo
#define vec_splat __builtin_vec_splat
#define vec_sr __builtin_vec_sr
#define vec_sra __builtin_vec_sra
#define vec_srl __builtin_vec_srl
#define vec_sro __builtin_vec_sro
#define vec_st __builtin_vec_st
#define vec_ste __builtin_vec_ste
#define vec_stl __builtin_vec_stl
#define vec_stvebx __builtin_vec_stvebx
#define vec_stvehx __builtin_vec_stvehx
#define vec_stvewx __builtin_vec_stvewx
/* Cell only intrinsics.  */
#ifdef __PPU__
#define vec_stvlx __builtin_vec_stvlx
#define vec_stvlxl __builtin_vec_stvlxl
#define vec_stvrx __builtin_vec_stvrx
#define vec_stvrxl __builtin_vec_stvrxl
#endif
#define vec_sub __builtin_vec_sub
#define vec_subs __builtin_vec_subs
#define vec_sum __builtin_vec_sum
#define vec_unpackh __builtin_vec_unpackh
#define vec_unpackl __builtin_vec_unpackl
#define vec_vaddubm __builtin_vec_vaddubm
#define vec_vaddubs __builtin_vec_vaddubs
#define vec_vadduhm __builtin_vec_vadduhm
#define vec_vadduhs __builtin_vec_vadduhs
#define vec_vadduwm __builtin_vec_vadduwm
#define vec_vadduws __builtin_vec_vadduws
#define vec_vcmpequb __builtin_vec_vcmpequb
#define vec_vcmpequh __builtin_vec_vcmpequh
#define vec_vcmpequw __builtin_vec_vcmpequw
#define vec_vmaxub __builtin_vec_vmaxub
#define vec_vmaxuh __builtin_vec_vmaxuh
#define vec_vmaxuw __builtin_vec_vmaxuw
#define vec_vminub __builtin_vec_vminub
#define vec_vminuh __builtin_vec_vminuh
#define vec_vminuw __builtin_vec_vminuw
#define vec_vmrghb __builtin_vec_vmrghb
#define vec_vmrghh __builtin_vec_vmrghh
#define vec_vmrghw __builtin_vec_vmrghw
#define vec_vmrglb __builtin_vec_vmrglb
#define vec_vmrglh __builtin_vec_vmrglh
#define vec_vmrglw __builtin_vec_vmrglw
#define vec_vpkuhum __builtin_vec_vpkuhum
#define vec_vpkuwum __builtin_vec_vpkuwum
#define vec_vrlb __builtin_vec_vrlb
#define vec_vrlh __builtin_vec_vrlh
#define vec_vrlw __builtin_vec_vrlw
#define vec_vslb __builtin_vec_vslb
#define vec_vslh __builtin_vec_vslh
#define vec_vslw __builtin_vec_vslw
#define vec_vspltb __builtin_vec_vspltb
#define vec_vsplth __builtin_vec_vsplth
#define vec_vspltw __builtin_vec_vspltw
#define vec_vsrab __builtin_vec_vsrab
#define vec_vsrah __builtin_vec_vsrah
#define vec_vsraw __builtin_vec_vsraw
#define vec_vsrb __builtin_vec_vsrb
#define vec_vsrh __builtin_vec_vsrh
#define vec_vsrw __builtin_vec_vsrw
#define vec_vsububs __builtin_vec_vsububs
#define vec_vsububm __builtin_vec_vsububm
#define vec_vsubuhm __builtin_vec_vsubuhm
#define vec_vsubuhs __builtin_vec_vsubuhs
#define vec_vsubuwm __builtin_vec_vsubuwm
#define vec_vsubuws __builtin_vec_vsubuws
#define vec_xor __builtin_vec_xor

#define vec_extract __builtin_vec_extract
#define vec_insert __builtin_vec_insert
#define vec_splats __builtin_vec_splats
#define vec_promote __builtin_vec_promote

/* Predicates.
   For C++, we use templates in order to allow non-parenthesized arguments.
   For C, instead, we use macros since non-parenthesized arguments were
   not allowed even in older GCC implementation of AltiVec.

   In the future, we may add more magic to the back-end, so that no
   one- or two-argument macros are used.  */

#ifdef __cplusplus__
#define __altivec_unary_pred(NAME, CALL) \
template <class T> int NAME (T a1) { return CALL; }

#define __altivec_scalar_pred(NAME, CALL) \
template <class T, class U> int NAME (T a1, U a2) { return CALL; }

/* Given the vec_step of a type, return the corresponding bool type.  */
template <int STEP> class __altivec_bool_ret { };
template <> class __altivec_bool_ret <4> {
  typedef __vector __bool int __ret;
};
template <> class __altivec_bool_ret <8> {
  typedef __vector __bool short __ret;
};
template <> class __altivec_bool_ret <16> {
  typedef __vector __bool char __ret;
};

/* Be very liberal in the pairs we accept.  Mistakes such as passing
   a `vector char' and `vector short' will be caught by the middle-end,
   while any attempt to detect them here would produce hard to understand
   error messages involving the implementation details of AltiVec.  */
#define __altivec_binary_pred(NAME, CALL) \
template <class T, class U> \
typename __altivec_bool_ret <vec_step (T)>::__ret \
NAME (T a1, U a2) \
{ \
  return CALL; \
}

__altivec_binary_pred(vec_cmplt,
  __builtin_vec_cmpgt (a2, a1))
__altivec_binary_pred(vec_cmple,
  __builtin_vec_cmpge (a2, a1))

__altivec_scalar_pred(vec_all_in,
  __builtin_altivec_vcmpbfp_p (__CR6_EQ, a1, a2))
__altivec_scalar_pred(vec_any_out,
  __builtin_altivec_vcmpbfp_p (__CR6_EQ_REV, a1, a2))

__altivec_unary_pred(vec_all_nan,
  __builtin_altivec_vcmpeqfp_p (__CR6_EQ, a1, a1))
__altivec_unary_pred(vec_any_nan,
  __builtin_altivec_vcmpeqfp_p (__CR6_LT_REV, a1, a1))

__altivec_unary_pred(vec_all_numeric,
  __builtin_altivec_vcmpeqfp_p (__CR6_LT, a1, a1))
__altivec_unary_pred(vec_any_numeric,
  __builtin_altivec_vcmpeqfp_p (__CR6_EQ_REV, a1, a1))

__altivec_scalar_pred(vec_all_eq,
  __builtin_vec_vcmpeq_p (__CR6_LT, a1, a2))
__altivec_scalar_pred(vec_all_ne,
  __builtin_vec_vcmpeq_p (__CR6_EQ, a1, a2))
__altivec_scalar_pred(vec_any_eq,
  __builtin_vec_vcmpeq_p (__CR6_EQ_REV, a1, a2))
__altivec_scalar_pred(vec_any_ne,
  __builtin_vec_vcmpeq_p (__CR6_LT_REV, a1, a2))

__altivec_scalar_pred(vec_all_gt,
  __builtin_vec_vcmpgt_p (__CR6_LT, a1, a2))
__altivec_scalar_pred(vec_all_lt,
  __builtin_vec_vcmpgt_p (__CR6_LT, a2, a1))
__altivec_scalar_pred(vec_any_gt,
  __builtin_vec_vcmpgt_p (__CR6_EQ_REV, a1, a2))
__altivec_scalar_pred(vec_any_lt,
  __builtin_vec_vcmpgt_p (__CR6_EQ_REV, a2, a1))

__altivec_scalar_pred(vec_all_ngt,
  __builtin_altivec_vcmpgtfp_p (__CR6_EQ, a1, a2))
__altivec_scalar_pred(vec_all_nlt,
  __builtin_altivec_vcmpgtfp_p (__CR6_EQ, a2, a1))
__altivec_scalar_pred(vec_any_ngt,
  __builtin_altivec_vcmpgtfp_p (__CR6_LT_REV, a1, a2))
__altivec_scalar_pred(vec_any_nlt,
  __builtin_altivec_vcmpgtfp_p (__CR6_LT_REV, a2, a1))

/* __builtin_vec_vcmpge_p is vcmpgefp for floating-point vector types,
   while for integer types it is converted to __builtin_vec_vcmpgt_p,
   with inverted args and condition code.  */
__altivec_scalar_pred(vec_all_le,
  __builtin_vec_vcmpge_p (__CR6_LT, a2, a1))
__altivec_scalar_pred(vec_all_ge,
  __builtin_vec_vcmpge_p (__CR6_LT, a1, a2))
__altivec_scalar_pred(vec_any_le,
  __builtin_vec_vcmpge_p (__CR6_EQ_REV, a2, a1))
__altivec_scalar_pred(vec_any_ge,
  __builtin_vec_vcmpge_p (__CR6_EQ_REV, a1, a2))

__altivec_scalar_pred(vec_all_nge,
  __builtin_altivec_vcmpgefp_p (__CR6_EQ, a1, a2))
__altivec_scalar_pred(vec_all_nle,
  __builtin_altivec_vcmpgefp_p (__CR6_EQ, a2, a1))
__altivec_scalar_pred(vec_any_nge,
  __builtin_altivec_vcmpgefp_p (__CR6_LT_REV, a1, a2))
__altivec_scalar_pred(vec_any_nle,
  __builtin_altivec_vcmpgefp_p (__CR6_LT_REV, a2, a1))

#undef __altivec_scalar_pred
#undef __altivec_unary_pred
#undef __altivec_binary_pred
#else
#define vec_cmplt(a1, a2) __builtin_vec_cmpgt ((a2), (a1))
#define vec_cmple(a1, a2) __builtin_vec_cmpge ((a2), (a1))

#define vec_all_in(a1, a2) __builtin_altivec_vcmpbfp_p (__CR6_EQ, (a1), (a2))
#define vec_any_out(a1, a2) __builtin_altivec_vcmpbfp_p (__CR6_EQ_REV, (a1), (a2))

#define vec_all_nan(a1) __builtin_altivec_vcmpeqfp_p (__CR6_EQ, (a1), (a1))
#define vec_any_nan(a1) __builtin_altivec_vcmpeqfp_p (__CR6_LT_REV, (a1), (a1))

#define vec_all_numeric(a1) __builtin_altivec_vcmpeqfp_p (__CR6_LT, (a1), (a1))
#define vec_any_numeric(a1) __builtin_altivec_vcmpeqfp_p (__CR6_EQ_REV, (a1), (a1))

#define vec_all_eq(a1, a2) __builtin_vec_vcmpeq_p (__CR6_LT, (a1), (a2))
#define vec_all_ne(a1, a2) __builtin_vec_vcmpeq_p (__CR6_EQ, (a1), (a2))
#define vec_any_eq(a1, a2) __builtin_vec_vcmpeq_p (__CR6_EQ_REV, (a1), (a2))
#define vec_any_ne(a1, a2) __builtin_vec_vcmpeq_p (__CR6_LT_REV, (a1), (a2))

#define vec_all_gt(a1, a2) __builtin_vec_vcmpgt_p (__CR6_LT, (a1), (a2))
#define vec_all_lt(a1, a2) __builtin_vec_vcmpgt_p (__CR6_LT, (a2), (a1))
#define vec_any_gt(a1, a2) __builtin_vec_vcmpgt_p (__CR6_EQ_REV, (a1), (a2))
#define vec_any_lt(a1, a2) __builtin_vec_vcmpgt_p (__CR6_EQ_REV, (a2), (a1))

#define vec_all_ngt(a1, a2) __builtin_altivec_vcmpgtfp_p (__CR6_EQ, (a1), (a2))
#define vec_all_nlt(a1, a2) __builtin_altivec_vcmpgtfp_p (__CR6_EQ, (a2), (a1))
#define vec_any_ngt(a1, a2) __builtin_altivec_vcmpgtfp_p (__CR6_LT_REV, (a1), (a2))
#define vec_any_nlt(a1, a2) __builtin_altivec_vcmpgtfp_p (__CR6_LT_REV, (a2), (a1))

/* __builtin_vec_vcmpge_p is vcmpgefp for floating-point vector types,
   while for integer types it is converted to __builtin_vec_vcmpgt_p,
   with inverted args and condition code.  */
#define vec_all_le(a1, a2) __builtin_vec_vcmpge_p (__CR6_LT, (a2), (a1))
#define vec_all_ge(a1, a2) __builtin_vec_vcmpge_p (__CR6_LT, (a1), (a2))
#define vec_any_le(a1, a2) __builtin_vec_vcmpge_p (__CR6_EQ_REV, (a2), (a1))
#define vec_any_ge(a1, a2) __builtin_vec_vcmpge_p (__CR6_EQ_REV, (a1), (a2))

#define vec_all_nge(a1, a2) __builtin_altivec_vcmpgefp_p (__CR6_EQ, (a1), (a2))
#define vec_all_nle(a1, a2) __builtin_altivec_vcmpgefp_p (__CR6_EQ, (a2), (a1))
#define vec_any_nge(a1, a2) __builtin_altivec_vcmpgefp_p (__CR6_LT_REV, (a1), (a2))
#define vec_any_nle(a1, a2) __builtin_altivec_vcmpgefp_p (__CR6_LT_REV, (a2), (a1))
#endif

/* These do not accept vectors, so they do not have a __builtin_vec_*
   counterpart.  */
#define vec_dss(x) __builtin_altivec_dss((x))
#define vec_dssall() __builtin_altivec_dssall ()
#define vec_mfvscr() ((__vector unsigned short) __builtin_altivec_mfvscr ())
#define vec_splat_s8(x) __builtin_altivec_vspltisb ((x))
#define vec_splat_s16(x) __builtin_altivec_vspltish ((x))
#define vec_splat_s32(x) __builtin_altivec_vspltisw ((x))
#define vec_splat_u8(x) ((__vector unsigned char) vec_splat_s8 ((x)))
#define vec_splat_u16(x) ((__vector unsigned short) vec_splat_s16 ((x)))
#define vec_splat_u32(x) ((__vector unsigned int) vec_splat_s32 ((x)))

/* This also accepts a type for its parameter, so it is not enough
   to #define vec_step to __builtin_vec_step.  */
#define vec_step(x) __builtin_vec_step (* (__typeof__ (x) *) 0)

#endif /* _ALTIVEC_H */