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Diffstat (limited to 'sysdeps/generic/fenv_private.h')
-rw-r--r-- | sysdeps/generic/fenv_private.h | 417 |
1 files changed, 417 insertions, 0 deletions
diff --git a/sysdeps/generic/fenv_private.h b/sysdeps/generic/fenv_private.h new file mode 100644 index 0000000000..912d23108f --- /dev/null +++ b/sysdeps/generic/fenv_private.h @@ -0,0 +1,417 @@ +/* Optimized inline fenv.h functions for libm. Generic version. + Copyright (C) 2011-2018 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#ifndef _FENV_PRIVATE_H +#define _FENV_PRIVATE_H 1 + +#include <fenv.h> +#include <get-rounding-mode.h> + +/* The standards only specify one variant of the fenv.h interfaces. + But at least for some architectures we can be more efficient if we + know what operations are going to be performed. Therefore we + define additional interfaces. By default they refer to the normal + interfaces. */ + +static __always_inline void +default_libc_feholdexcept (fenv_t *e) +{ + (void) __feholdexcept (e); +} + +#ifndef libc_feholdexcept +# define libc_feholdexcept default_libc_feholdexcept +#endif +#ifndef libc_feholdexceptf +# define libc_feholdexceptf default_libc_feholdexcept +#endif +#ifndef libc_feholdexceptl +# define libc_feholdexceptl default_libc_feholdexcept +#endif + +static __always_inline void +default_libc_fesetround (int r) +{ + (void) __fesetround (r); +} + +#ifndef libc_fesetround +# define libc_fesetround default_libc_fesetround +#endif +#ifndef libc_fesetroundf +# define libc_fesetroundf default_libc_fesetround +#endif +#ifndef libc_fesetroundl +# define libc_fesetroundl default_libc_fesetround +#endif + +static __always_inline void +default_libc_feholdexcept_setround (fenv_t *e, int r) +{ + __feholdexcept (e); + __fesetround (r); +} + +#ifndef libc_feholdexcept_setround +# define libc_feholdexcept_setround default_libc_feholdexcept_setround +#endif +#ifndef libc_feholdexcept_setroundf +# define libc_feholdexcept_setroundf default_libc_feholdexcept_setround +#endif +#ifndef libc_feholdexcept_setroundl +# define libc_feholdexcept_setroundl default_libc_feholdexcept_setround +#endif + +#ifndef libc_feholdsetround_53bit +# define libc_feholdsetround_53bit libc_feholdsetround +#endif + +#ifndef libc_fetestexcept +# define libc_fetestexcept fetestexcept +#endif +#ifndef libc_fetestexceptf +# define libc_fetestexceptf fetestexcept +#endif +#ifndef libc_fetestexceptl +# define libc_fetestexceptl fetestexcept +#endif + +static __always_inline void +default_libc_fesetenv (fenv_t *e) +{ + (void) __fesetenv (e); +} + +#ifndef libc_fesetenv +# define libc_fesetenv default_libc_fesetenv +#endif +#ifndef libc_fesetenvf +# define libc_fesetenvf default_libc_fesetenv +#endif +#ifndef libc_fesetenvl +# define libc_fesetenvl default_libc_fesetenv +#endif + +static __always_inline void +default_libc_feupdateenv (fenv_t *e) +{ + (void) __feupdateenv (e); +} + +#ifndef libc_feupdateenv +# define libc_feupdateenv default_libc_feupdateenv +#endif +#ifndef libc_feupdateenvf +# define libc_feupdateenvf default_libc_feupdateenv +#endif +#ifndef libc_feupdateenvl +# define libc_feupdateenvl default_libc_feupdateenv +#endif + +#ifndef libc_feresetround_53bit +# define libc_feresetround_53bit libc_feresetround +#endif + +static __always_inline int +default_libc_feupdateenv_test (fenv_t *e, int ex) +{ + int ret = fetestexcept (ex); + __feupdateenv (e); + return ret; +} + +#ifndef libc_feupdateenv_test +# define libc_feupdateenv_test default_libc_feupdateenv_test +#endif +#ifndef libc_feupdateenv_testf +# define libc_feupdateenv_testf default_libc_feupdateenv_test +#endif +#ifndef libc_feupdateenv_testl +# define libc_feupdateenv_testl default_libc_feupdateenv_test +#endif + +/* Save and set the rounding mode. The use of fenv_t to store the old mode + allows a target-specific version of this function to avoid converting the + rounding mode from the fpu format. By default we have no choice but to + manipulate the entire env. */ + +#ifndef libc_feholdsetround +# define libc_feholdsetround libc_feholdexcept_setround +#endif +#ifndef libc_feholdsetroundf +# define libc_feholdsetroundf libc_feholdexcept_setroundf +#endif +#ifndef libc_feholdsetroundl +# define libc_feholdsetroundl libc_feholdexcept_setroundl +#endif + +/* ... and the reverse. */ + +#ifndef libc_feresetround +# define libc_feresetround libc_feupdateenv +#endif +#ifndef libc_feresetroundf +# define libc_feresetroundf libc_feupdateenvf +#endif +#ifndef libc_feresetroundl +# define libc_feresetroundl libc_feupdateenvl +#endif + +/* ... and a version that also discards exceptions. */ + +#ifndef libc_feresetround_noex +# define libc_feresetround_noex libc_fesetenv +#endif +#ifndef libc_feresetround_noexf +# define libc_feresetround_noexf libc_fesetenvf +#endif +#ifndef libc_feresetround_noexl +# define libc_feresetround_noexl libc_fesetenvl +#endif + +#ifndef HAVE_RM_CTX +# define HAVE_RM_CTX 0 +#endif + + +/* Default implementation using standard fenv functions. + Avoid unnecessary rounding mode changes by first checking the + current rounding mode. Note the use of __glibc_unlikely is + important for performance. */ + +static __always_inline void +default_libc_feholdsetround_ctx (struct rm_ctx *ctx, int round) +{ + ctx->updated_status = false; + + /* Update rounding mode only if different. */ + if (__glibc_unlikely (round != get_rounding_mode ())) + { + ctx->updated_status = true; + __fegetenv (&ctx->env); + __fesetround (round); + } +} + +static __always_inline void +default_libc_feresetround_ctx (struct rm_ctx *ctx) +{ + /* Restore the rounding mode if updated. */ + if (__glibc_unlikely (ctx->updated_status)) + __feupdateenv (&ctx->env); +} + +static __always_inline void +default_libc_feholdsetround_noex_ctx (struct rm_ctx *ctx, int round) +{ + /* Save exception flags and rounding mode, and disable exception + traps. */ + __feholdexcept (&ctx->env); + + /* Update rounding mode only if different. */ + if (__glibc_unlikely (round != get_rounding_mode ())) + __fesetround (round); +} + +static __always_inline void +default_libc_feresetround_noex_ctx (struct rm_ctx *ctx) +{ + /* Restore exception flags and rounding mode. */ + __fesetenv (&ctx->env); +} + +#if HAVE_RM_CTX +/* Set/Restore Rounding Modes only when necessary. If defined, these functions + set/restore floating point state only if the state needed within the lexical + block is different from the current state. This saves a lot of time when + the floating point unit is much slower than the fixed point units. */ + +# ifndef libc_feholdsetround_noex_ctx +# define libc_feholdsetround_noex_ctx libc_feholdsetround_ctx +# endif +# ifndef libc_feholdsetround_noexf_ctx +# define libc_feholdsetround_noexf_ctx libc_feholdsetroundf_ctx +# endif +# ifndef libc_feholdsetround_noexl_ctx +# define libc_feholdsetround_noexl_ctx libc_feholdsetroundl_ctx +# endif + +# ifndef libc_feresetround_noex_ctx +# define libc_feresetround_noex_ctx libc_fesetenv_ctx +# endif +# ifndef libc_feresetround_noexf_ctx +# define libc_feresetround_noexf_ctx libc_fesetenvf_ctx +# endif +# ifndef libc_feresetround_noexl_ctx +# define libc_feresetround_noexl_ctx libc_fesetenvl_ctx +# endif + +#else + +# define libc_feholdsetround_ctx default_libc_feholdsetround_ctx +# define libc_feresetround_ctx default_libc_feresetround_ctx +# define libc_feholdsetround_noex_ctx default_libc_feholdsetround_noex_ctx +# define libc_feresetround_noex_ctx default_libc_feresetround_noex_ctx + +# define libc_feholdsetroundf_ctx libc_feholdsetround_ctx +# define libc_feholdsetroundl_ctx libc_feholdsetround_ctx +# define libc_feresetroundf_ctx libc_feresetround_ctx +# define libc_feresetroundl_ctx libc_feresetround_ctx + +# define libc_feholdsetround_noexf_ctx libc_feholdsetround_noex_ctx +# define libc_feholdsetround_noexl_ctx libc_feholdsetround_noex_ctx +# define libc_feresetround_noexf_ctx libc_feresetround_noex_ctx +# define libc_feresetround_noexl_ctx libc_feresetround_noex_ctx + +#endif + +#ifndef libc_feholdsetround_53bit_ctx +# define libc_feholdsetround_53bit_ctx libc_feholdsetround_ctx +#endif +#ifndef libc_feresetround_53bit_ctx +# define libc_feresetround_53bit_ctx libc_feresetround_ctx +#endif + +#define SET_RESTORE_ROUND_GENERIC(RM,ROUNDFUNC,CLEANUPFUNC) \ + struct rm_ctx ctx __attribute__((cleanup (CLEANUPFUNC ## _ctx))); \ + ROUNDFUNC ## _ctx (&ctx, (RM)) + +/* Set the rounding mode within a lexical block. Restore the rounding mode to + the value at the start of the block. The exception mode must be preserved. + Exceptions raised within the block must be set in the exception flags. + Non-stop mode may be enabled inside the block. */ + +#define SET_RESTORE_ROUND(RM) \ + SET_RESTORE_ROUND_GENERIC (RM, libc_feholdsetround, libc_feresetround) +#define SET_RESTORE_ROUNDF(RM) \ + SET_RESTORE_ROUND_GENERIC (RM, libc_feholdsetroundf, libc_feresetroundf) +#define SET_RESTORE_ROUNDL(RM) \ + SET_RESTORE_ROUND_GENERIC (RM, libc_feholdsetroundl, libc_feresetroundl) + +/* Set the rounding mode within a lexical block. Restore the rounding mode to + the value at the start of the block. The exception mode must be preserved. + Exceptions raised within the block must be discarded, and exception flags + are restored to the value at the start of the block. + Non-stop mode must be enabled inside the block. */ + +#define SET_RESTORE_ROUND_NOEX(RM) \ + SET_RESTORE_ROUND_GENERIC (RM, libc_feholdsetround_noex, \ + libc_feresetround_noex) +#define SET_RESTORE_ROUND_NOEXF(RM) \ + SET_RESTORE_ROUND_GENERIC (RM, libc_feholdsetround_noexf, \ + libc_feresetround_noexf) +#define SET_RESTORE_ROUND_NOEXL(RM) \ + SET_RESTORE_ROUND_GENERIC (RM, libc_feholdsetround_noexl, \ + libc_feresetround_noexl) + +/* Like SET_RESTORE_ROUND, but also set rounding precision to 53 bits. */ +#define SET_RESTORE_ROUND_53BIT(RM) \ + SET_RESTORE_ROUND_GENERIC (RM, libc_feholdsetround_53bit, \ + libc_feresetround_53bit) + +/* When no floating-point exceptions are defined in <fenv.h>, make + feraiseexcept ignore its argument so that unconditional + feraiseexcept calls do not cause errors for undefined exceptions. + Define it to expand to a void expression so that any calls testing + the result of feraiseexcept do produce errors. */ +#if FE_ALL_EXCEPT == 0 +# define feraiseexcept(excepts) ((void) 0) +# define __feraiseexcept(excepts) ((void) 0) +#endif + +/* Similarly, most <fenv.h> functions have trivial implementations in + the absence of support for floating-point exceptions and rounding + modes. */ + +#if !FE_HAVE_ROUNDING_MODES +# if FE_ALL_EXCEPT == 0 +extern inline int +fegetenv (fenv_t *__e) +{ + return 0; +} + +extern inline int +__fegetenv (fenv_t *__e) +{ + return 0; +} + +extern inline int +feholdexcept (fenv_t *__e) +{ + return 0; +} + +extern inline int +__feholdexcept (fenv_t *__e) +{ + return 0; +} + +extern inline int +fesetenv (const fenv_t *__e) +{ + return 0; +} + +extern inline int +__fesetenv (const fenv_t *__e) +{ + return 0; +} + +extern inline int +feupdateenv (const fenv_t *__e) +{ + return 0; +} + +extern inline int +__feupdateenv (const fenv_t *__e) +{ + return 0; +} +# endif + +extern inline int +fegetround (void) +{ + return FE_TONEAREST; +} + +extern inline int +__fegetround (void) +{ + return FE_TONEAREST; +} + +extern inline int +fesetround (int __d) +{ + return 0; +} + +extern inline int +__fesetround (int __d) +{ + return 0; +} +#endif + +#endif /* fenv_private.h. */ |