From 7e308604ee0aa67bc37f37d6f69ed41481c427a0 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Sun, 31 Oct 2010 03:03:38 +0100 Subject: libm: improve readability of math.h; expand comments and docs Signed-off-by: Denys Vlasenko --- docs/defines.txt | 16 ++++++--- include/complex.h | 10 +++--- include/math.h | 52 ++++++++++++++---------------- libc/sysdeps/linux/alpha/bits/mathdef.h | 8 ++--- libc/sysdeps/linux/common/bits/mathcalls.h | 13 +++++--- libc/sysdeps/linux/i386/bits/mathinline.h | 2 +- 6 files changed, 56 insertions(+), 45 deletions(-) diff --git a/docs/defines.txt b/docs/defines.txt index 23991813e..8f37788dc 100644 --- a/docs/defines.txt +++ b/docs/defines.txt @@ -16,11 +16,18 @@ _LARGEFILE[64]_SOURCE _FILE_OFFSET_BITS ??? -__NTH(fct) __THROW -__REDIRECT(name, proto, alias) -__REDIRECT_NTH(name, proto, alias) - ??? + Function annotation "I do not throw anything". +__NTH(func(params)) + Function annotation "I do not throw anything". + Needed for situatuons when it's unclear on what side of "func(params)" + the "throw()" or "attribute((nothrow))" should eventually appear. + Messy, eh? + +return_type __REDIRECT(name, (params), alias) + declare alias to "name(params)" +return_type __REDIRECT_NTH(name, (params), alias) + declare alias to "name(params) __THROW" __BIG_ENDIAN 4321 __LITTLE_ENDIAN 1234 @@ -49,6 +56,7 @@ _EXTERN_INLINE __extern_inline Defined to "extern inline", modulo gcc/C standard deviations. Can't be used by user to play tricks as with _EXTERN_INLINE. + internal_function Used to modify function's calling convention, if "standard" one is suboptimal. Examples: diff --git a/include/complex.h b/include/complex.h index 94fb6ea44..8779bbcd0 100644 --- a/include/complex.h +++ b/include/complex.h @@ -54,13 +54,13 @@ __BEGIN_DECLS so we can easily declare each function as both `name' and `__name', and can declare the float versions `namef' and `__namef'. */ -#define __MATHCALL(function, args) \ - __MATHDECL (_Mdouble_complex_,function, args) +#define __MATHCALL(function, args) \ + __MATHDECL(_Mdouble_complex_,function, args) #define __MATHDECL(type, function, args) \ - __MATHDECL_1(type, function, args); \ - __MATHDECL_1(type, __CONCAT(__,function), args) + __MATHDECL_1(type, function, args); \ + __MATHDECL_1(type, __CONCAT(__,function), args) #define __MATHDECL_1(type, function, args) \ - extern type __MATH_PRECNAME(function) args __THROW + extern type __MATH_PRECNAME(function) args __THROW #define _Mdouble_ double #define __MATH_PRECNAME(name) name diff --git a/include/math.h b/include/math.h index 91ebd64bb..d3f86f9c1 100644 --- a/include/math.h +++ b/include/math.h @@ -53,40 +53,40 @@ __BEGIN_DECLS and can declare the float versions `namef' and `__namef'. */ #define __MATHDECL_1(type,function,suffix,args) \ - extern type __MATH_PRECNAME(function,suffix) args __THROW + extern type __MATH_PRECNAME(function,suffix) args __THROW #define __MATHDECL(type,function,suffix,args) \ - __MATHDECL_1(type,function,suffix,args); + __MATHDECL_1(type,function,suffix,args); -#define __MATHCALL(function,suffix,args) \ - __MATHDECL(_Mdouble_,function,suffix,args) +#define __MATHCALL(function,suffix,args) \ + __MATHDECL(_Mdouble_,function,suffix,args) #define __MATHDECLX(type,function,suffix,args,attrib) \ - __MATHDECL_1(type,function,suffix,args) __attribute__ (attrib); \ - __MATH_maybe_libm_hidden_proto(function) + __MATHDECL_1(type,function,suffix,args) __attribute__ (attrib); \ + __MATH_maybe_libm_hidden_proto(function) -#define __MATHCALLX(function,suffix,args,attrib) \ - __MATHDECLX(_Mdouble_,function,suffix,args,attrib) +#define __MATHCALLX(function,suffix,args,attrib) \ + __MATHDECLX(_Mdouble_,function,suffix,args,attrib) /* Decls which are also used internally in libm. Only the main variant is used internally, no need to try to avoid relocs for the {l,f} variants. */ #define __MATHDECLI(type,function,suffix,args) \ - __MATHDECL_1(type,function,suffix,args); \ - __MATH_maybe_libm_hidden_proto(function) + __MATHDECL_1(type,function,suffix,args); \ + __MATH_maybe_libm_hidden_proto(function) -#define __MATHCALLI(function,suffix,args) \ - __MATHDECLI(_Mdouble_,function,suffix,args) +#define __MATHCALLI(function,suffix,args) \ + __MATHDECLI(_Mdouble_,function,suffix,args) /* Private helpers for purely macro impls below. Only make __foo{,f,l} visible but not (the macro-only) foo. */ #if defined _LIBC # define __MATHDECL_PRIV(type,function,suffix,args,attrib) \ - __MATHDECL_1(type,__CONCAT(__,function),suffix,args) __attribute__ (attrib); \ - libm_hidden_proto(__MATH_PRECNAME(__##function,suffix)) + __MATHDECL_1(type,__CONCAT(__,function),suffix,args) __attribute__ (attrib); \ + libm_hidden_proto(__MATH_PRECNAME(__##function,suffix)) #else # define __MATHDECL_PRIV(type,function,suffix,args,attrib) \ - __MATHDECL_1(type,__CONCAT(__,function),suffix,args) __attribute__ (attrib); + __MATHDECL_1(type,__CONCAT(__,function),suffix,args) __attribute__ (attrib); #endif @@ -139,17 +139,15 @@ __BEGIN_DECLS # ifdef __LDBL_COMPAT # ifdef __USE_ISOC99 -extern float __nldbl_nexttowardf (float __x, long double __y) - __THROW __attribute__ ((__const__)); +extern float __nldbl_nexttowardf (float __x, long double __y) __THROW + __attribute__ ((__const__)); # ifdef __REDIRECT_NTH -extern float __REDIRECT_NTH (nexttowardf, (float __x, long double __y), - __nldbl_nexttowardf) - __attribute__ ((__const__)); -extern double __REDIRECT_NTH (nexttoward, (double __x, long double __y), - nextafter) __attribute__ ((__const__)); -extern long double __REDIRECT_NTH (nexttowardl, - (long double __x, long double __y), - nextafter) __attribute__ ((__const__)); +extern float __REDIRECT_NTH (nexttowardf, (float __x, long double __y), __nldbl_nexttowardf) + __attribute__ ((__const__)); +extern double __REDIRECT_NTH (nexttoward, (double __x, long double __y), nextafter) + __attribute__ ((__const__)); +extern long double __REDIRECT_NTH (nexttowardl, (long double __x, long double __y), nextafter) + __attribute__ ((__const__)); # endif # endif @@ -158,9 +156,9 @@ extern long double __REDIRECT_NTH (nexttowardl, # undef __MATHDECL_1 # define __MATHDECL_2(type,function,suffix,args,alias) \ - extern type __REDIRECT_NTH(__MATH_PRECNAME(function,suffix),args,alias) + extern type __REDIRECT_NTH(__MATH_PRECNAME(function,suffix),args,alias) # define __MATHDECL_1(type,function,suffix,args) \ - __MATHDECL_2(type,function,suffix,args,__CONCAT(function,suffix)) + __MATHDECL_2(type,function,suffix,args,__CONCAT(function,suffix)) # endif # define __MATH_maybe_libm_hidden_proto(x) diff --git a/libc/sysdeps/linux/alpha/bits/mathdef.h b/libc/sysdeps/linux/alpha/bits/mathdef.h index 2e5258230..615eb9db6 100644 --- a/libc/sysdeps/linux/alpha/bits/mathdef.h +++ b/libc/sysdeps/linux/alpha/bits/mathdef.h @@ -44,12 +44,12 @@ typedef double double_t; /* Due to an ABI change, we need to remap the complex float symbols. */ # define _Mdouble_ float # define __MATHCALL(function, args) \ - __MATHDECL (_Complex float, function, args) + __MATHDECL(_Complex float, function, args) # define __MATHDECL(type, function, args) \ - __MATHDECL_1(type, function##f, args, __c1_##function##f); \ - __MATHDECL_1(type, __##function##f, args, __c1_##function##f) + __MATHDECL_1(type, function##f, args, __c1_##function##f); \ + __MATHDECL_1(type, __##function##f, args, __c1_##function##f) # define __MATHDECL_1(type, function, args, alias) \ - extern type function args __asm__(#alias) __THROW + extern type function args __asm__(#alias) __THROW # include diff --git a/libc/sysdeps/linux/common/bits/mathcalls.h b/libc/sysdeps/linux/common/bits/mathcalls.h index 3772b7d0d..1e92b527e 100644 --- a/libc/sysdeps/linux/common/bits/mathcalls.h +++ b/libc/sysdeps/linux/common/bits/mathcalls.h @@ -48,11 +48,16 @@ #endif -/* __MATHCALLX and __MATHCALLI include libm_hidden_def +/* __MATHCALLX(type,function,[suffix],args,attrib) and + * __MATHCALLI(type,function,[suffix],args) include libm_hidden_def * (for "double" versions only, xxxf and xxxl do not get this treatment). - * __MATHCALL does not. - * __MATHDECL_PRIV includes libm_hidden_def (always) - * and declares __foo, not foo. + * + * __MATHDECL(type,function,[suffix],args) does not. + * __MATHCALL(function,[suffix],args) also does not + * (it is just a shortcut to __MATHDECL(_Mdouble_,function,[suffix],args)). + * + * __MATHDECL_PRIV(type,function,[suffix],args,attrib) + * includes libm_hidden_def (always) and declares __foo, not foo. */ diff --git a/libc/sysdeps/linux/i386/bits/mathinline.h b/libc/sysdeps/linux/i386/bits/mathinline.h index 53cbcb2b3..9e67182d5 100644 --- a/libc/sysdeps/linux/i386/bits/mathinline.h +++ b/libc/sysdeps/linux/i386/bits/mathinline.h @@ -206,7 +206,7 @@ __NTH (__signbitl (long double __x)) __MATH_INLINE float_type __NTH (func (float_type __x)) \ { \ register float_type __result; \ - __asm__ __volatile__ (op : "=t" (__result) : params); \ + __asm__ __volatile__ (op : "=t" (__result) : params); \ return __result; \ } -- cgit v1.2.3