| @c Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc. |
| @c This is part of the GCC manual. |
| @c For copying conditions, see the file gcc.texi. |
| @c Contributed by Aldy Hernandez <aldy@quesejoda.com> |
| |
| @node Libgcc |
| @chapter The GCC low-level runtime library |
| |
| GCC provides a low-level runtime library, @file{libgcc.a} or |
| @file{libgcc_s.so.1} on some platforms. GCC generates calls to |
| routines in this library automatically, whenever it needs to perform |
| some operation that is too complicated to emit inline code for. |
| |
| Most of the routines in @code{libgcc} handle arithmetic operations |
| that the target processor cannot perform directly. This includes |
| integer multiply and divide on some machines, and all floating-point |
| operations on other machines. @code{libgcc} also includes routines |
| for exception handling, and a handful of miscellaneous operations. |
| |
| Some of these routines can be defined in mostly machine-independent C@. |
| Others must be hand-written in assembly language for each processor |
| that needs them. |
| |
| GCC will also generate calls to C library routines, such as |
| @code{memcpy} and @code{memset}, in some cases. The set of routines |
| that GCC may possibly use is documented in @ref{Other |
| Builtins,,,gcc, Using the GNU Compiler Collection (GCC)}. |
| |
| These routines take arguments and return values of a specific machine |
| mode, not a specific C type. @xref{Machine Modes}, for an explanation |
| of this concept. For illustrative purposes, in this chapter the |
| floating point type @code{float} is assumed to correspond to @code{SFmode}; |
| @code{double} to @code{DFmode}; and @code{@w{long double}} to both |
| @code{TFmode} and @code{XFmode}. Similarly, the integer types @code{int} |
| and @code{@w{unsigned int}} correspond to @code{SImode}; @code{long} and |
| @code{@w{unsigned long}} to @code{DImode}; and @code{@w{long long}} and |
| @code{@w{unsigned long long}} to @code{TImode}. |
| |
| @menu |
| * Integer library routines:: |
| * Soft float library routines:: |
| * Decimal float library routines:: |
| * Exception handling routines:: |
| * Miscellaneous routines:: |
| @end menu |
| |
| @node Integer library routines |
| @section Routines for integer arithmetic |
| |
| The integer arithmetic routines are used on platforms that don't provide |
| hardware support for arithmetic operations on some modes. |
| |
| @subsection Arithmetic functions |
| |
| @deftypefn {Runtime Function} int __ashlsi3 (int @var{a}, int @var{b}) |
| @deftypefnx {Runtime Function} long __ashldi3 (long @var{a}, int @var{b}) |
| @deftypefnx {Runtime Function} {long long} __ashlti3 (long long @var{a}, int @var{b}) |
| These functions return the result of shifting @var{a} left by @var{b} bits. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __ashrsi3 (int @var{a}, int @var{b}) |
| @deftypefnx {Runtime Function} long __ashrdi3 (long @var{a}, int @var{b}) |
| @deftypefnx {Runtime Function} {long long} __ashrti3 (long long @var{a}, int @var{b}) |
| These functions return the result of arithmetically shifting @var{a} right |
| by @var{b} bits. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __divsi3 (int @var{a}, int @var{b}) |
| @deftypefnx {Runtime Function} long __divdi3 (long @var{a}, long @var{b}) |
| @deftypefnx {Runtime Function} {long long} __divti3 (long long @var{a}, long long @var{b}) |
| These functions return the quotient of the signed division of @var{a} and |
| @var{b}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __lshrsi3 (int @var{a}, int @var{b}) |
| @deftypefnx {Runtime Function} long __lshrdi3 (long @var{a}, int @var{b}) |
| @deftypefnx {Runtime Function} {long long} __lshrti3 (long long @var{a}, int @var{b}) |
| These functions return the result of logically shifting @var{a} right by |
| @var{b} bits. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __modsi3 (int @var{a}, int @var{b}) |
| @deftypefnx {Runtime Function} long __moddi3 (long @var{a}, long @var{b}) |
| @deftypefnx {Runtime Function} {long long} __modti3 (long long @var{a}, long long @var{b}) |
| These functions return the remainder of the signed division of @var{a} |
| and @var{b}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __mulsi3 (int @var{a}, int @var{b}) |
| @deftypefnx {Runtime Function} long __muldi3 (long @var{a}, long @var{b}) |
| @deftypefnx {Runtime Function} {long long} __multi3 (long long @var{a}, long long @var{b}) |
| These functions return the product of @var{a} and @var{b}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} long __negdi2 (long @var{a}) |
| @deftypefnx {Runtime Function} {long long} __negti2 (long long @var{a}) |
| These functions return the negation of @var{a}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} {unsigned int} __udivsi3 (unsigned int @var{a}, unsigned int @var{b}) |
| @deftypefnx {Runtime Function} {unsigned long} __udivdi3 (unsigned long @var{a}, unsigned long @var{b}) |
| @deftypefnx {Runtime Function} {unsigned long long} __udivti3 (unsigned long long @var{a}, unsigned long long @var{b}) |
| These functions return the quotient of the unsigned division of @var{a} |
| and @var{b}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} {unsigned long} __udivmoddi3 (unsigned long @var{a}, unsigned long @var{b}, unsigned long *@var{c}) |
| @deftypefnx {Runtime Function} {unsigned long long} __udivti3 (unsigned long long @var{a}, unsigned long long @var{b}, unsigned long long *@var{c}) |
| These functions calculate both the quotient and remainder of the unsigned |
| division of @var{a} and @var{b}. The return value is the quotient, and |
| the remainder is placed in variable pointed to by @var{c}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} {unsigned int} __umodsi3 (unsigned int @var{a}, unsigned int @var{b}) |
| @deftypefnx {Runtime Function} {unsigned long} __umoddi3 (unsigned long @var{a}, unsigned long @var{b}) |
| @deftypefnx {Runtime Function} {unsigned long long} __umodti3 (unsigned long long @var{a}, unsigned long long @var{b}) |
| These functions return the remainder of the unsigned division of @var{a} |
| and @var{b}. |
| @end deftypefn |
| |
| @subsection Comparison functions |
| |
| The following functions implement integral comparisons. These functions |
| implement a low-level compare, upon which the higher level comparison |
| operators (such as less than and greater than or equal to) can be |
| constructed. The returned values lie in the range zero to two, to allow |
| the high-level operators to be implemented by testing the returned |
| result using either signed or unsigned comparison. |
| |
| @deftypefn {Runtime Function} int __cmpdi2 (long @var{a}, long @var{b}) |
| @deftypefnx {Runtime Function} int __cmpti2 (long long @var{a}, long long @var{b}) |
| These functions perform a signed comparison of @var{a} and @var{b}. If |
| @var{a} is less than @var{b}, they return 0; if @var{a} is greater than |
| @var{b}, they return 2; and if @var{a} and @var{b} are equal they return 1. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __ucmpdi2 (unsigned long @var{a}, unsigned long @var{b}) |
| @deftypefnx {Runtime Function} int __ucmpti2 (unsigned long long @var{a}, unsigned long long @var{b}) |
| These functions perform an unsigned comparison of @var{a} and @var{b}. |
| If @var{a} is less than @var{b}, they return 0; if @var{a} is greater than |
| @var{b}, they return 2; and if @var{a} and @var{b} are equal they return 1. |
| @end deftypefn |
| |
| @subsection Trapping arithmetic functions |
| |
| The following functions implement trapping arithmetic. These functions |
| call the libc function @code{abort} upon signed arithmetic overflow. |
| |
| @deftypefn {Runtime Function} int __absvsi2 (int @var{a}) |
| @deftypefnx {Runtime Function} long __absvdi2 (long @var{a}) |
| These functions return the absolute value of @var{a}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __addvsi3 (int @var{a}, int @var{b}) |
| @deftypefnx {Runtime Function} long __addvdi3 (long @var{a}, long @var{b}) |
| These functions return the sum of @var{a} and @var{b}; that is |
| @code{@var{a} + @var{b}}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __mulvsi3 (int @var{a}, int @var{b}) |
| @deftypefnx {Runtime Function} long __mulvdi3 (long @var{a}, long @var{b}) |
| The functions return the product of @var{a} and @var{b}; that is |
| @code{@var{a} * @var{b}}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __negvsi2 (int @var{a}) |
| @deftypefnx {Runtime Function} long __negvdi2 (long @var{a}) |
| These functions return the negation of @var{a}; that is @code{-@var{a}}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __subvsi3 (int @var{a}, int @var{b}) |
| @deftypefnx {Runtime Function} long __subvdi3 (long @var{a}, long @var{b}) |
| These functions return the difference between @var{b} and @var{a}; |
| that is @code{@var{a} - @var{b}}. |
| @end deftypefn |
| |
| @subsection Bit operations |
| |
| @deftypefn {Runtime Function} int __clzsi2 (int @var{a}) |
| @deftypefnx {Runtime Function} int __clzdi2 (long @var{a}) |
| @deftypefnx {Runtime Function} int __clzti2 (long long @var{a}) |
| These functions return the number of leading 0-bits in @var{a}, starting |
| at the most significant bit position. If @var{a} is zero, the result is |
| undefined. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __ctzsi2 (int @var{a}) |
| @deftypefnx {Runtime Function} int __ctzdi2 (long @var{a}) |
| @deftypefnx {Runtime Function} int __ctzti2 (long long @var{a}) |
| These functions return the number of trailing 0-bits in @var{a}, starting |
| at the least significant bit position. If @var{a} is zero, the result is |
| undefined. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __ffsdi2 (long @var{a}) |
| @deftypefnx {Runtime Function} int __ffsti2 (long long @var{a}) |
| These functions return the index of the least significant 1-bit in @var{a}, |
| or the value zero if @var{a} is zero. The least significant bit is index |
| one. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __paritysi2 (int @var{a}) |
| @deftypefnx {Runtime Function} int __paritydi2 (long @var{a}) |
| @deftypefnx {Runtime Function} int __parityti2 (long long @var{a}) |
| These functions return the value zero if the number of bits set in |
| @var{a} is even, and the value one otherwise. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __popcountsi2 (int @var{a}) |
| @deftypefnx {Runtime Function} int __popcountdi2 (long @var{a}) |
| @deftypefnx {Runtime Function} int __popcountti2 (long long @var{a}) |
| These functions return the number of bits set in @var{a}. |
| @end deftypefn |
| @c APPLE LOCAL begin mainline bswap |
| @deftypefn {Runtime Function} int32_t __bswapsi2 (int32_t @var{a}) |
| @deftypefnx {Runtime Function} int64_t __bswapdi2 (int64_t @var{a}) |
| These functions return the @var{a} byteswapped. |
| @end deftypefn |
| @c APPLE LOCAL end mainline bswap |
| |
| @node Soft float library routines |
| @section Routines for floating point emulation |
| @cindex soft float library |
| @cindex arithmetic library |
| @cindex math library |
| @opindex msoft-float |
| |
| The software floating point library is used on machines which do not |
| have hardware support for floating point. It is also used whenever |
| @option{-msoft-float} is used to disable generation of floating point |
| instructions. (Not all targets support this switch.) |
| |
| For compatibility with other compilers, the floating point emulation |
| routines can be renamed with the @code{DECLARE_LIBRARY_RENAMES} macro |
| (@pxref{Library Calls}). In this section, the default names are used. |
| |
| Presently the library does not support @code{XFmode}, which is used |
| for @code{long double} on some architectures. |
| |
| @subsection Arithmetic functions |
| |
| @deftypefn {Runtime Function} float __addsf3 (float @var{a}, float @var{b}) |
| @deftypefnx {Runtime Function} double __adddf3 (double @var{a}, double @var{b}) |
| @deftypefnx {Runtime Function} {long double} __addtf3 (long double @var{a}, long double @var{b}) |
| @deftypefnx {Runtime Function} {long double} __addxf3 (long double @var{a}, long double @var{b}) |
| These functions return the sum of @var{a} and @var{b}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} float __subsf3 (float @var{a}, float @var{b}) |
| @deftypefnx {Runtime Function} double __subdf3 (double @var{a}, double @var{b}) |
| @deftypefnx {Runtime Function} {long double} __subtf3 (long double @var{a}, long double @var{b}) |
| @deftypefnx {Runtime Function} {long double} __subxf3 (long double @var{a}, long double @var{b}) |
| These functions return the difference between @var{b} and @var{a}; |
| that is, @w{@math{@var{a} - @var{b}}}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} float __mulsf3 (float @var{a}, float @var{b}) |
| @deftypefnx {Runtime Function} double __muldf3 (double @var{a}, double @var{b}) |
| @deftypefnx {Runtime Function} {long double} __multf3 (long double @var{a}, long double @var{b}) |
| @deftypefnx {Runtime Function} {long double} __mulxf3 (long double @var{a}, long double @var{b}) |
| These functions return the product of @var{a} and @var{b}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} float __divsf3 (float @var{a}, float @var{b}) |
| @deftypefnx {Runtime Function} double __divdf3 (double @var{a}, double @var{b}) |
| @deftypefnx {Runtime Function} {long double} __divtf3 (long double @var{a}, long double @var{b}) |
| @deftypefnx {Runtime Function} {long double} __divxf3 (long double @var{a}, long double @var{b}) |
| These functions return the quotient of @var{a} and @var{b}; that is, |
| @w{@math{@var{a} / @var{b}}}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} float __negsf2 (float @var{a}) |
| @deftypefnx {Runtime Function} double __negdf2 (double @var{a}) |
| @deftypefnx {Runtime Function} {long double} __negtf2 (long double @var{a}) |
| @deftypefnx {Runtime Function} {long double} __negxf2 (long double @var{a}) |
| These functions return the negation of @var{a}. They simply flip the |
| sign bit, so they can produce negative zero and negative NaN@. |
| @end deftypefn |
| |
| @subsection Conversion functions |
| |
| @deftypefn {Runtime Function} double __extendsfdf2 (float @var{a}) |
| @deftypefnx {Runtime Function} {long double} __extendsftf2 (float @var{a}) |
| @deftypefnx {Runtime Function} {long double} __extendsfxf2 (float @var{a}) |
| @deftypefnx {Runtime Function} {long double} __extenddftf2 (double @var{a}) |
| @deftypefnx {Runtime Function} {long double} __extenddfxf2 (double @var{a}) |
| These functions extend @var{a} to the wider mode of their return |
| type. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} double __truncxfdf2 (long double @var{a}) |
| @deftypefnx {Runtime Function} double __trunctfdf2 (long double @var{a}) |
| @deftypefnx {Runtime Function} float __truncxfsf2 (long double @var{a}) |
| @deftypefnx {Runtime Function} float __trunctfsf2 (long double @var{a}) |
| @deftypefnx {Runtime Function} float __truncdfsf2 (double @var{a}) |
| These functions truncate @var{a} to the narrower mode of their return |
| type, rounding toward zero. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __fixsfsi (float @var{a}) |
| @deftypefnx {Runtime Function} int __fixdfsi (double @var{a}) |
| @deftypefnx {Runtime Function} int __fixtfsi (long double @var{a}) |
| @deftypefnx {Runtime Function} int __fixxfsi (long double @var{a}) |
| These functions convert @var{a} to a signed integer, rounding toward zero. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} long __fixsfdi (float @var{a}) |
| @deftypefnx {Runtime Function} long __fixdfdi (double @var{a}) |
| @deftypefnx {Runtime Function} long __fixtfdi (long double @var{a}) |
| @deftypefnx {Runtime Function} long __fixxfdi (long double @var{a}) |
| These functions convert @var{a} to a signed long, rounding toward zero. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} {long long} __fixsfti (float @var{a}) |
| @deftypefnx {Runtime Function} {long long} __fixdfti (double @var{a}) |
| @deftypefnx {Runtime Function} {long long} __fixtfti (long double @var{a}) |
| @deftypefnx {Runtime Function} {long long} __fixxfti (long double @var{a}) |
| These functions convert @var{a} to a signed long long, rounding toward zero. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} {unsigned int} __fixunssfsi (float @var{a}) |
| @deftypefnx {Runtime Function} {unsigned int} __fixunsdfsi (double @var{a}) |
| @deftypefnx {Runtime Function} {unsigned int} __fixunstfsi (long double @var{a}) |
| @deftypefnx {Runtime Function} {unsigned int} __fixunsxfsi (long double @var{a}) |
| These functions convert @var{a} to an unsigned integer, rounding |
| toward zero. Negative values all become zero. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} {unsigned long} __fixunssfdi (float @var{a}) |
| @deftypefnx {Runtime Function} {unsigned long} __fixunsdfdi (double @var{a}) |
| @deftypefnx {Runtime Function} {unsigned long} __fixunstfdi (long double @var{a}) |
| @deftypefnx {Runtime Function} {unsigned long} __fixunsxfdi (long double @var{a}) |
| These functions convert @var{a} to an unsigned long, rounding |
| toward zero. Negative values all become zero. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} {unsigned long long} __fixunssfti (float @var{a}) |
| @deftypefnx {Runtime Function} {unsigned long long} __fixunsdfti (double @var{a}) |
| @deftypefnx {Runtime Function} {unsigned long long} __fixunstfti (long double @var{a}) |
| @deftypefnx {Runtime Function} {unsigned long long} __fixunsxfti (long double @var{a}) |
| These functions convert @var{a} to an unsigned long long, rounding |
| toward zero. Negative values all become zero. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} float __floatsisf (int @var{i}) |
| @deftypefnx {Runtime Function} double __floatsidf (int @var{i}) |
| @deftypefnx {Runtime Function} {long double} __floatsitf (int @var{i}) |
| @deftypefnx {Runtime Function} {long double} __floatsixf (int @var{i}) |
| These functions convert @var{i}, a signed integer, to floating point. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} float __floatdisf (long @var{i}) |
| @deftypefnx {Runtime Function} double __floatdidf (long @var{i}) |
| @deftypefnx {Runtime Function} {long double} __floatditf (long @var{i}) |
| @deftypefnx {Runtime Function} {long double} __floatdixf (long @var{i}) |
| These functions convert @var{i}, a signed long, to floating point. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} float __floattisf (long long @var{i}) |
| @deftypefnx {Runtime Function} double __floattidf (long long @var{i}) |
| @deftypefnx {Runtime Function} {long double} __floattitf (long long @var{i}) |
| @deftypefnx {Runtime Function} {long double} __floattixf (long long @var{i}) |
| These functions convert @var{i}, a signed long long, to floating point. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} float __floatunsisf (unsigned int @var{i}) |
| @deftypefnx {Runtime Function} double __floatunsidf (unsigned int @var{i}) |
| @deftypefnx {Runtime Function} {long double} __floatunsitf (unsigned int @var{i}) |
| @deftypefnx {Runtime Function} {long double} __floatunsixf (unsigned int @var{i}) |
| These functions convert @var{i}, an unsigned integer, to floating point. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} float __floatundisf (unsigned long @var{i}) |
| @deftypefnx {Runtime Function} double __floatundidf (unsigned long @var{i}) |
| @deftypefnx {Runtime Function} {long double} __floatunditf (unsigned long @var{i}) |
| @deftypefnx {Runtime Function} {long double} __floatundixf (unsigned long @var{i}) |
| These functions convert @var{i}, an unsigned long, to floating point. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} float __floatuntisf (unsigned long long @var{i}) |
| @deftypefnx {Runtime Function} double __floatuntidf (unsigned long long @var{i}) |
| @deftypefnx {Runtime Function} {long double} __floatuntitf (unsigned long long @var{i}) |
| @deftypefnx {Runtime Function} {long double} __floatuntixf (unsigned long long @var{i}) |
| These functions convert @var{i}, an unsigned long long, to floating point. |
| @end deftypefn |
| |
| @subsection Comparison functions |
| |
| There are two sets of basic comparison functions. |
| |
| @deftypefn {Runtime Function} int __cmpsf2 (float @var{a}, float @var{b}) |
| @deftypefnx {Runtime Function} int __cmpdf2 (double @var{a}, double @var{b}) |
| @deftypefnx {Runtime Function} int __cmptf2 (long double @var{a}, long double @var{b}) |
| These functions calculate @math{a <=> b}. That is, if @var{a} is less |
| than @var{b}, they return @minus{}1; if @var{a} is greater than @var{b}, they |
| return 1; and if @var{a} and @var{b} are equal they return 0. If |
| either argument is NaN they return 1, but you should not rely on this; |
| if NaN is a possibility, use one of the higher-level comparison |
| functions. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __unordsf2 (float @var{a}, float @var{b}) |
| @deftypefnx {Runtime Function} int __unorddf2 (double @var{a}, double @var{b}) |
| @deftypefnx {Runtime Function} int __unordtf2 (long double @var{a}, long double @var{b}) |
| These functions return a nonzero value if either argument is NaN, otherwise 0. |
| @end deftypefn |
| |
| There is also a complete group of higher level functions which |
| correspond directly to comparison operators. They implement the ISO C |
| semantics for floating-point comparisons, taking NaN into account. |
| Pay careful attention to the return values defined for each set. |
| Under the hood, all of these routines are implemented as |
| |
| @smallexample |
| if (__unord@var{X}f2 (a, b)) |
| return @var{E}; |
| return __cmp@var{X}f2 (a, b); |
| @end smallexample |
| |
| @noindent |
| where @var{E} is a constant chosen to give the proper behavior for |
| NaN@. Thus, the meaning of the return value is different for each set. |
| Do not rely on this implementation; only the semantics documented |
| below are guaranteed. |
| |
| @deftypefn {Runtime Function} int __eqsf2 (float @var{a}, float @var{b}) |
| @deftypefnx {Runtime Function} int __eqdf2 (double @var{a}, double @var{b}) |
| @deftypefnx {Runtime Function} int __eqtf2 (long double @var{a}, long double @var{b}) |
| These functions return zero if neither argument is NaN, and @var{a} and |
| @var{b} are equal. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __nesf2 (float @var{a}, float @var{b}) |
| @deftypefnx {Runtime Function} int __nedf2 (double @var{a}, double @var{b}) |
| @deftypefnx {Runtime Function} int __netf2 (long double @var{a}, long double @var{b}) |
| These functions return a nonzero value if either argument is NaN, or |
| if @var{a} and @var{b} are unequal. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __gesf2 (float @var{a}, float @var{b}) |
| @deftypefnx {Runtime Function} int __gedf2 (double @var{a}, double @var{b}) |
| @deftypefnx {Runtime Function} int __getf2 (long double @var{a}, long double @var{b}) |
| These functions return a value greater than or equal to zero if |
| neither argument is NaN, and @var{a} is greater than or equal to |
| @var{b}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __ltsf2 (float @var{a}, float @var{b}) |
| @deftypefnx {Runtime Function} int __ltdf2 (double @var{a}, double @var{b}) |
| @deftypefnx {Runtime Function} int __lttf2 (long double @var{a}, long double @var{b}) |
| These functions return a value less than zero if neither argument is |
| NaN, and @var{a} is strictly less than @var{b}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __lesf2 (float @var{a}, float @var{b}) |
| @deftypefnx {Runtime Function} int __ledf2 (double @var{a}, double @var{b}) |
| @deftypefnx {Runtime Function} int __letf2 (long double @var{a}, long double @var{b}) |
| These functions return a value less than or equal to zero if neither |
| argument is NaN, and @var{a} is less than or equal to @var{b}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __gtsf2 (float @var{a}, float @var{b}) |
| @deftypefnx {Runtime Function} int __gtdf2 (double @var{a}, double @var{b}) |
| @deftypefnx {Runtime Function} int __gttf2 (long double @var{a}, long double @var{b}) |
| These functions return a value greater than zero if neither argument |
| is NaN, and @var{a} is strictly greater than @var{b}. |
| @end deftypefn |
| |
| @subsection Other floating-point functions |
| |
| @deftypefn {Runtime Function} float __powisf2 (float @var{a}, int @var{b}) |
| @deftypefnx {Runtime Function} double __powidf2 (double @var{a}, int @var{b}) |
| @deftypefnx {Runtime Function} {long double} __powitf2 (long double @var{a}, int @var{b}) |
| @deftypefnx {Runtime Function} {long double} __powixf2 (long double @var{a}, int @var{b}) |
| These functions convert raise @var{a} to the power @var{b}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} {complex float} __mulsc3 (float @var{a}, float @var{b}, float @var{c}, float @var{d}) |
| @deftypefnx {Runtime Function} {complex double} __muldc3 (double @var{a}, double @var{b}, double @var{c}, double @var{d}) |
| @deftypefnx {Runtime Function} {complex long double} __multc3 (long double @var{a}, long double @var{b}, long double @var{c}, long double @var{d}) |
| @deftypefnx {Runtime Function} {complex long double} __mulxc3 (long double @var{a}, long double @var{b}, long double @var{c}, long double @var{d}) |
| These functions return the product of @math{@var{a} + i@var{b}} and |
| @math{@var{c} + i@var{d}}, following the rules of C99 Annex G@. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} {complex float} __divsc3 (float @var{a}, float @var{b}, float @var{c}, float @var{d}) |
| @deftypefnx {Runtime Function} {complex double} __divdc3 (double @var{a}, double @var{b}, double @var{c}, double @var{d}) |
| @deftypefnx {Runtime Function} {complex long double} __divtc3 (long double @var{a}, long double @var{b}, long double @var{c}, long double @var{d}) |
| @deftypefnx {Runtime Function} {complex long double} __divxc3 (long double @var{a}, long double @var{b}, long double @var{c}, long double @var{d}) |
| These functions return the quotient of @math{@var{a} + i@var{b}} and |
| @math{@var{c} + i@var{d}} (i.e., @math{(@var{a} + i@var{b}) / (@var{c} |
| + i@var{d})}), following the rules of C99 Annex G@. |
| @end deftypefn |
| |
| @node Decimal float library routines |
| @section Routines for decimal floating point emulation |
| @cindex decimal float library |
| @cindex IEEE-754R |
| |
| The software decimal floating point library implements IEEE 754R |
| decimal floating point arithmetic and is only activated on selected |
| targets. |
| |
| @subsection Arithmetic functions |
| |
| @deftypefn {Runtime Function} _Decimal32 __addsd3 (_Decimal32 @var{a}, _Decimal32 @var{b}) |
| @deftypefnx {Runtime Function} _Decimal64 __adddd3 (_Decimal64 @var{a}, _Decimal64 @var{b}) |
| @deftypefnx {Runtime Function} _Decimal128 __addtd3 (_Decimal128 @var{a}, _Decimal128 @var{b}) |
| These functions return the sum of @var{a} and @var{b}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} _Decimal32 __subsd3 (_Decimal32 @var{a}, _Decimal32 @var{b}) |
| @deftypefnx {Runtime Function} _Decimal64 __subdd3 (_Decimal64 @var{a}, _Decimal64 @var{b}) |
| @deftypefnx {Runtime Function} _Decimal128 __subtd3 (_Decimal128 @var{a}, _Decimal128 @var{b}) |
| These functions return the difference between @var{b} and @var{a}; |
| that is, @w{@math{@var{a} - @var{b}}}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} _Decimal32 __mulsd3 (_Decimal32 @var{a}, _Decimal32 @var{b}) |
| @deftypefnx {Runtime Function} _Decimal64 __muldd3 (_Decimal64 @var{a}, _Decimal64 @var{b}) |
| @deftypefnx {Runtime Function} _Decimal128 __multd3 (_Decimal128 @var{a}, _Decimal128 @var{b}) |
| These functions return the product of @var{a} and @var{b}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} _Decimal32 __divsd3 (_Decimal32 @var{a}, _Decimal32 @var{b}) |
| @deftypefnx {Runtime Function} _Decimal64 __divdd3 (_Decimal64 @var{a}, _Decimal64 @var{b}) |
| @deftypefnx {Runtime Function} _Decimal128 __divtd3 (_Decimal128 @var{a}, _Decimal128 @var{b}) |
| These functions return the quotient of @var{a} and @var{b}; that is, |
| @w{@math{@var{a} / @var{b}}}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} _Decimal32 __negsd2 (_Decimal32 @var{a}) |
| @deftypefnx {Runtime Function} _Decimal64 __negdd2 (_Decimal64 @var{a}) |
| @deftypefnx {Runtime Function} _Decimal128 __negtd2 (_Decimal128 @var{a}) |
| These functions return the negation of @var{a}. They simply flip the |
| sign bit, so they can produce negative zero and negative NaN@. |
| @end deftypefn |
| |
| @subsection Conversion functions |
| |
| @c DFP/DFP conversions |
| @deftypefn {Runtime Function} _Decimal64 __extendsddd2 (_Decimal32 @var{a}) |
| @deftypefnx {Runtime Function} _Decimal128 __extendsdtd2 (_Decimal32 @var{a}) |
| @deftypefnx {Runtime Function} _Decimal128 __extendddtd2 (_Decimal64 @var{a}) |
| @c DFP/binary FP conversions |
| @deftypefnx {Runtime Function} _Decimal32 __extendsfsd (float @var{a}) |
| @deftypefnx {Runtime Function} double __extendsddf (_Decimal32 @var{a}) |
| @deftypefnx {Runtime Function} {long double} __extendsdxf (_Decimal32 @var{a}) |
| @deftypefnx {Runtime Function} _Decimal64 __extendsfdd (float @var{a}) |
| @deftypefnx {Runtime Function} _Decimal64 __extenddfdd (double @var{a}) |
| @deftypefnx {Runtime Function} {long double} __extendddxf (_Decimal64 @var{a}) |
| @deftypefnx {Runtime Function} _Decimal128 __extendsftd (float @var{a}) |
| @deftypefnx {Runtime Function} _Decimal128 __extenddftd (double @var{a}) |
| @deftypefnx {Runtime Function} _Decimal128 __extendxftd ({long double} @var{a}) |
| These functions extend @var{a} to the wider mode of their return type. |
| @end deftypefn |
| |
| @c DFP/DFP conversions |
| @deftypefn {Runtime Function} _Decimal32 __truncddsd2 (_Decimal64 @var{a}) |
| @deftypefnx {Runtime Function} _Decimal32 __trunctdsd2 (_Decimal128 @var{a}) |
| @deftypefnx {Runtime Function} _Decimal64 __trunctddd2 (_Decimal128 @var{a}) |
| @c DFP/binary FP conversions |
| @deftypefnx {Runtime Function} float __truncsdsf (_Decimal32 @var{a}) |
| @deftypefnx {Runtime Function} _Decimal32 __truncdfsd (double @var{a}) |
| @deftypefnx {Runtime Function} _Decimal32 __truncxfsd ({long double} @var{a}) |
| @deftypefnx {Runtime Function} float __truncddsf (_Decimal64 @var{a}) |
| @deftypefnx {Runtime Function} double __truncdddf (_Decimal64 @var{a}) |
| @deftypefnx {Runtime Function} _Decimal64 __truncxfdd ({long double} @var{a}) |
| @deftypefnx {Runtime Function} float __trunctdsf (_Decimal128 @var{a}) |
| @deftypefnx {Runtime Function} double __trunctddf (_Decimal128 @var{a}) |
| @deftypefnx {Runtime Function} {long double} __trunctdxf (_Decimal128 @var{a}) |
| These functions truncate @var{a} to the narrower mode of their return |
| type. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __fixsdsi (_Decimal32 @var{a}) |
| @deftypefnx {Runtime Function} int __fixddsi (_Decimal64 @var{a}) |
| @deftypefnx {Runtime Function} int __fixtdsi (_Decimal128 @var{a}) |
| These functions convert @var{a} to a signed integer. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} long __fixsddi (_Decimal32 @var{a}) |
| @deftypefnx {Runtime Function} long __fixdddi (_Decimal64 @var{a}) |
| @deftypefnx {Runtime Function} long __fixtddi (_Decimal128 @var{a}) |
| These functions convert @var{a} to a signed long. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} {unsigned int} __fixunssdsi (_Decimal32 @var{a}) |
| @deftypefnx {Runtime Function} {unsigned int} __fixunsddsi (_Decimal64 @var{a}) |
| @deftypefnx {Runtime Function} {unsigned int} __fixunstdsi (_Decimal128 @var{a}) |
| These functions convert @var{a} to an unsigned integer. Negative values all become zero. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} {unsigned long} __fixunssddi (_Decimal32 @var{a}) |
| @deftypefnx {Runtime Function} {unsigned long} __fixunsdddi (_Decimal64 @var{a}) |
| @deftypefnx {Runtime Function} {unsigned long} __fixunstddi (_Decimal128 @var{a}) |
| These functions convert @var{a} to an unsigned long. Negative values |
| all become zero. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} _Decimal32 __floatsisd (int @var{i}) |
| @deftypefnx {Runtime Function} _Decimal64 __floatsidd (int @var{i}) |
| @deftypefnx {Runtime Function} _Decimal128 __floatsitd (int @var{i}) |
| These functions convert @var{i}, a signed integer, to decimal floating point. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} _Decimal32 __floatdisd (long @var{i}) |
| @deftypefnx {Runtime Function} _Decimal64 __floatdidd (long @var{i}) |
| @deftypefnx {Runtime Function} _Decimal128 __floatditd (long @var{i}) |
| These functions convert @var{i}, a signed long, to decimal floating point. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} _Decimal32 __floatunssisd (unsigned int @var{i}) |
| @deftypefnx {Runtime Function} _Decimal64 __floatunssidd (unsigned int @var{i}) |
| @deftypefnx {Runtime Function} _Decimal128 __floatunssitd (unsigned int @var{i}) |
| These functions convert @var{i}, an unsigned integer, to decimal floating point. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} _Decimal32 __floatunsdisd (unsigned long @var{i}) |
| @deftypefnx {Runtime Function} _Decimal64 __floatunsdidd (unsigned long @var{i}) |
| @deftypefnx {Runtime Function} _Decimal128 __floatunsditd (unsigned long @var{i}) |
| These functions convert @var{i}, an unsigned long, to decimal floating point. |
| @end deftypefn |
| |
| @subsection Comparison functions |
| |
| @deftypefn {Runtime Function} int __unordsd2 (_Decimal32 @var{a}, _Decimal32 @var{b}) |
| @deftypefnx {Runtime Function} int __unorddd2 (_Decimal64 @var{a}, _Decimal64 @var{b}) |
| @deftypefnx {Runtime Function} int __unordtd2 (_Decimal128 @var{a}, _Decimal128 @var{b}) |
| These functions return a nonzero value if either argument is NaN, otherwise 0. |
| @end deftypefn |
| |
| There is also a complete group of higher level functions which |
| correspond directly to comparison operators. They implement the ISO C |
| semantics for floating-point comparisons, taking NaN into account. |
| Pay careful attention to the return values defined for each set. |
| Under the hood, all of these routines are implemented as |
| |
| @smallexample |
| if (__unord@var{X}d2 (a, b)) |
| return @var{E}; |
| return __cmp@var{X}d2 (a, b); |
| @end smallexample |
| |
| @noindent |
| where @var{E} is a constant chosen to give the proper behavior for |
| NaN@. Thus, the meaning of the return value is different for each set. |
| Do not rely on this implementation; only the semantics documented |
| below are guaranteed. |
| |
| @deftypefn {Runtime Function} int __eqsd2 (_Decimal32 @var{a}, _Decimal32 @var{b}) |
| @deftypefnx {Runtime Function} int __eqdd2 (_Decimal64 @var{a}, _Decimal64 @var{b}) |
| @deftypefnx {Runtime Function} int __eqtd2 (_Decimal128 @var{a}, _Decimal128 @var{b}) |
| These functions return zero if neither argument is NaN, and @var{a} and |
| @var{b} are equal. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __nesd2 (_Decimal32 @var{a}, _Decimal32 @var{b}) |
| @deftypefnx {Runtime Function} int __nedd2 (_Decimal64 @var{a}, _Decimal64 @var{b}) |
| @deftypefnx {Runtime Function} int __netd2 (_Decimal128 @var{a}, _Decimal128 @var{b}) |
| These functions return a nonzero value if either argument is NaN, or |
| if @var{a} and @var{b} are unequal. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __gesd2 (_Decimal32 @var{a}, _Decimal32 @var{b}) |
| @deftypefnx {Runtime Function} int __gedd2 (_Decimal64 @var{a}, _Decimal64 @var{b}) |
| @deftypefnx {Runtime Function} int __getd2 (_Decimal128 @var{a}, _Decimal128 @var{b}) |
| These functions return a value greater than or equal to zero if |
| neither argument is NaN, and @var{a} is greater than or equal to |
| @var{b}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __ltsd2 (_Decimal32 @var{a}, _Decimal32 @var{b}) |
| @deftypefnx {Runtime Function} int __ltdd2 (_Decimal64 @var{a}, _Decimal64 @var{b}) |
| @deftypefnx {Runtime Function} int __lttd2 (_Decimal128 @var{a}, _Decimal128 @var{b}) |
| These functions return a value less than zero if neither argument is |
| NaN, and @var{a} is strictly less than @var{b}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __lesd2 (_Decimal32 @var{a}, _Decimal32 @var{b}) |
| @deftypefnx {Runtime Function} int __ledd2 (_Decimal64 @var{a}, _Decimal64 @var{b}) |
| @deftypefnx {Runtime Function} int __letd2 (_Decimal128 @var{a}, _Decimal128 @var{b}) |
| These functions return a value less than or equal to zero if neither |
| argument is NaN, and @var{a} is less than or equal to @var{b}. |
| @end deftypefn |
| |
| @deftypefn {Runtime Function} int __gtsd2 (_Decimal32 @var{a}, _Decimal32 @var{b}) |
| @deftypefnx {Runtime Function} int __gtdd2 (_Decimal64 @var{a}, _Decimal64 @var{b}) |
| @deftypefnx {Runtime Function} int __gttd2 (_Decimal128 @var{a}, _Decimal128 @var{b}) |
| These functions return a value greater than zero if neither argument |
| is NaN, and @var{a} is strictly greater than @var{b}. |
| @end deftypefn |
| |
| @node Exception handling routines |
| @section Language-independent routines for exception handling |
| |
| document me! |
| |
| @smallexample |
| _Unwind_DeleteException |
| _Unwind_Find_FDE |
| _Unwind_ForcedUnwind |
| _Unwind_GetGR |
| _Unwind_GetIP |
| _Unwind_GetLanguageSpecificData |
| _Unwind_GetRegionStart |
| _Unwind_GetTextRelBase |
| _Unwind_GetDataRelBase |
| _Unwind_RaiseException |
| _Unwind_Resume |
| _Unwind_SetGR |
| _Unwind_SetIP |
| _Unwind_FindEnclosingFunction |
| _Unwind_SjLj_Register |
| _Unwind_SjLj_Unregister |
| _Unwind_SjLj_RaiseException |
| _Unwind_SjLj_ForcedUnwind |
| _Unwind_SjLj_Resume |
| __deregister_frame |
| __deregister_frame_info |
| __deregister_frame_info_bases |
| __register_frame |
| __register_frame_info |
| __register_frame_info_bases |
| __register_frame_info_table |
| __register_frame_info_table_bases |
| __register_frame_table |
| @end smallexample |
| |
| @node Miscellaneous routines |
| @section Miscellaneous runtime library routines |
| |
| @subsection Cache control functions |
| @deftypefn {Runtime Function} void __clear_cache (char *@var{beg}, char *@var{end}) |
| This function clears the instruction cache between @var{beg} and @var{end}. |
| @end deftypefn |