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-rw-r--r--ChangeLog49
-rw-r--r--include/fenv.h10
-rw-r--r--sysdeps/generic/math_private.h55
-rw-r--r--sysdeps/i386/fpu/fenv_private.h173
4 files changed, 273 insertions, 14 deletions
diff --git a/ChangeLog b/ChangeLog
index f42d563..66ac05a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,52 @@
+2013-06-12 Siddhesh Poyarekar <siddhesh@redhat.com>
+
+ * include/fenv.h: Include stdbool.h.
+ (struct rm_ctx): New structure.
+ * sysdeps/generic/math_private.h (SET_RESTORE_ROUND_GENERIC):
+ Define macro.
+ (SET_RESTORE_ROUND): Define using SET_RESTORE_ROUND_GENERIC.
+ (SET_RESTORE_ROUNDF): Likewise.
+ (SET_RESTORE_ROUNDL): Likewise.
+ (SET_RESTORE_ROUND_NOEX): Likewise.
+ (SET_RESTORE_ROUND_NOEXF): Likewise.
+ (SET_RESTORE_ROUND_NOEXL): Likewise.
+ (SET_RESTORE_ROUND_53BIT): Likewise.
+ [HAVE_RM_CTX] (libc_feresetround_noex_ctx): Define macro.
+ (libc_feresetround_noexf_ctx): Likewise.
+ (libc_feresetround_noexl_ctx): Likewise.
+ (libc_feholdsetround_53bit_ctx): Likewise.
+ (libc_feresetround_53bit_ctx): Likewise.
+ * sysdeps/i386/fpu/fenv_private.h (HAVE_RM_CTX): Define macro.
+ (libc_feholdexcept_setround_sse_ctx): New function.
+ (libc_fesetenv_sse_ctx): Likewise.
+ (libc_feupdateenv_sse_ctx): Likewise.
+ (libc_feholdexcept_setround_387_prec_ctx): Likewise.
+ (libc_feholdexcept_setround_387_ctx): Likewise.
+ (libc_feholdexcept_setround_387_53bit_ctx): Likewise.
+ (libc_feholdsetround_387_prec_ctx): Likewise.
+ (libc_feholdsetround_387_ctx): Likewise.
+ (libc_feholdsetround_387_53bit_ctx): Likewise.
+ (libc_feholdsetround_sse_ctx): Likewise.
+ (libc_feresetround_sse_ctx): Likewise.
+ (libc_feresetround_387_ctx): Likewise.
+ (libc_feupdateenv_387_ctx): Likewise.
+ (libc_feholdexcept_setroundf_ctx): Define macro.
+ (libc_fesetenvf_ctx): Likewise.
+ (libc_feupdateenvf_ctx): Likewise.
+ (libc_feholdsetroundf_ctx): Likewise.
+ (libc_feresetroundf_ctx): Likewise.
+ (libc_feholdexcept_setround_ctx): Likewise.
+ (libc_fesetenv_ctx): Likewise.
+ (libc_feupdateenv_ctx): Likewise.
+ (libc_feholdsetround_ctx): Likewise.
+ (libc_feresetround_ctx): Likewise.
+ (libc_feholdexcept_setroundl_ctx): Likewise.
+ (libc_feupdateenvl_ctx): Likewise.
+ (libc_feholdsetroundl_ctx): Likewise.
+ (libc_feresetroundl_ctx): Likewise.
+ [!__SSE2_MATH__] (libc_feholdsetround_53bit_ctx): Likewise.
+ (libc_feresetround_53bit_ctx): Likewise.
+
2013-06-11 Siddhesh Poyarekar <siddhesh@redhat.com>
* locale/iso-639.def: Convert to UTF-8.
diff --git a/include/fenv.h b/include/fenv.h
index ed6d139..9f90d17 100644
--- a/include/fenv.h
+++ b/include/fenv.h
@@ -1,5 +1,6 @@
#ifndef _FENV_H
#include <math/fenv.h>
+#include <stdbool.h>
#ifndef _ISOMAC
/* Now define the internal interfaces. */
@@ -23,4 +24,13 @@ libm_hidden_proto (fetestexcept)
libm_hidden_proto (feclearexcept)
#endif
+/* Rounding mode context. This allows functions to set/restore rounding mode
+ only when the desired rounding mode is different from the current rounding
+ mode. */
+struct rm_ctx
+{
+ fenv_t env;
+ bool updated_status;
+};
+
#endif
diff --git a/sysdeps/generic/math_private.h b/sysdeps/generic/math_private.h
index e98360d..c0fc03d 100644
--- a/sysdeps/generic/math_private.h
+++ b/sysdeps/generic/math_private.h
@@ -553,35 +553,62 @@ default_libc_feupdateenv_test (fenv_t *e, int ex)
# define libc_feresetround_noexl libc_fesetenvl
#endif
+#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_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
+
+# 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))
+#else
+# define SET_RESTORE_ROUND_GENERIC(RM, ROUNDFUNC, CLEANUPFUNC) \
+ fenv_t __libc_save_rm __attribute__((cleanup(CLEANUPFUNC))); \
+ ROUNDFUNC (&__libc_save_rm, (RM))
+#endif
+
/* Save and restore the rounding mode within a lexical block. */
#define SET_RESTORE_ROUND(RM) \
- fenv_t __libc_save_rm __attribute__((cleanup(libc_feresetround))); \
- libc_feholdsetround (&__libc_save_rm, (RM))
+ SET_RESTORE_ROUND_GENERIC (RM, libc_feholdsetround, libc_feresetround)
#define SET_RESTORE_ROUNDF(RM) \
- fenv_t __libc_save_rm __attribute__((cleanup(libc_feresetroundf))); \
- libc_feholdsetroundf (&__libc_save_rm, (RM))
+ SET_RESTORE_ROUND_GENERIC (RM, libc_feholdsetroundf, libc_feresetroundf)
#define SET_RESTORE_ROUNDL(RM) \
- fenv_t __libc_save_rm __attribute__((cleanup(libc_feresetroundl))); \
- libc_feholdsetroundl (&__libc_save_rm, (RM))
+ SET_RESTORE_ROUND_GENERIC (RM, libc_feholdsetroundl, libc_feresetroundl)
/* Save and restore the rounding mode within a lexical block, and also
the set of exceptions raised within the block may be discarded. */
#define SET_RESTORE_ROUND_NOEX(RM) \
- fenv_t __libc_save_rm __attribute__((cleanup(libc_feresetround_noex))); \
- libc_feholdsetround (&__libc_save_rm, (RM))
+ SET_RESTORE_ROUND_GENERIC (RM, libc_feholdsetround, libc_feresetround_noex)
#define SET_RESTORE_ROUND_NOEXF(RM) \
- fenv_t __libc_save_rm __attribute__((cleanup(libc_feresetround_noexf))); \
- libc_feholdsetroundf (&__libc_save_rm, (RM))
+ SET_RESTORE_ROUND_GENERIC (RM, libc_feholdsetroundf, libc_feresetround_noexf)
#define SET_RESTORE_ROUND_NOEXL(RM) \
- fenv_t __libc_save_rm __attribute__((cleanup(libc_feresetround_noexl))); \
- libc_feholdsetroundl (&__libc_save_rm, (RM))
+ SET_RESTORE_ROUND_GENERIC (RM, libc_feholdsetroundl, libc_feresetround_noexl)
/* Like SET_RESTORE_ROUND, but also set rounding precision to 53 bits. */
#define SET_RESTORE_ROUND_53BIT(RM) \
- fenv_t __libc_save_rm __attribute__((cleanup(libc_feresetround_53bit))); \
- libc_feholdsetround_53bit (&__libc_save_rm, (RM))
+ SET_RESTORE_ROUND_GENERIC (RM, libc_feholdsetround_53bit, \
+ libc_feresetround_53bit)
#define __nan(str) \
(__builtin_constant_p (str) && str[0] == '\0' ? NAN : __nan (str))
diff --git a/sysdeps/i386/fpu/fenv_private.h b/sysdeps/i386/fpu/fenv_private.h
index 1f8336c..3998387 100644
--- a/sysdeps/i386/fpu/fenv_private.h
+++ b/sysdeps/i386/fpu/fenv_private.h
@@ -322,6 +322,179 @@ libc_feresetround_387 (fenv_t *e)
# define libc_feholdsetround_53bit libc_feholdsetround_387_53bit
#endif
+/* We have support for rounding mode context. */
+#define HAVE_RM_CTX 1
+
+static __always_inline void
+libc_feholdexcept_setround_sse_ctx (struct rm_ctx *ctx, int r)
+{
+ unsigned int mxcsr, new_mxcsr;
+ asm (STMXCSR " %0" : "=m" (*&mxcsr));
+ new_mxcsr = ((mxcsr | 0x1f80) & ~0x603f) | (r << 3);
+
+ ctx->env.__mxcsr = mxcsr;
+ if (__glibc_unlikely (mxcsr != new_mxcsr))
+ {
+ asm volatile (LDMXCSR " %0" : : "m" (*&new_mxcsr));
+ ctx->updated_status = true;
+ }
+ else
+ ctx->updated_status = false;
+}
+
+/* Unconditional since we want to overwrite any exceptions that occurred in the
+ context. This is also why all fehold* functions unconditionally write into
+ ctx->env. */
+static __always_inline void
+libc_fesetenv_sse_ctx (struct rm_ctx *ctx)
+{
+ libc_fesetenv_sse (&ctx->env);
+}
+
+static __always_inline void
+libc_feupdateenv_sse_ctx (struct rm_ctx *ctx)
+{
+ if (__glibc_unlikely (ctx->updated_status))
+ libc_feupdateenv_test_sse (&ctx->env, 0);
+}
+
+static __always_inline void
+libc_feholdexcept_setround_387_prec_ctx (struct rm_ctx *ctx, int r)
+{
+ libc_feholdexcept_387 (&ctx->env);
+
+ fpu_control_t cw = ctx->env.__control_word;
+ fpu_control_t old_cw = cw;
+ cw &= ~(_FPU_RC_ZERO | _FPU_EXTENDED);
+ cw |= r | 0x3f;
+
+ if (__glibc_unlikely (old_cw != cw))
+ {
+ _FPU_SETCW (cw);
+ ctx->updated_status = true;
+ }
+ else
+ ctx->updated_status = false;
+}
+
+static __always_inline void
+libc_feholdexcept_setround_387_ctx (struct rm_ctx *ctx, int r)
+{
+ libc_feholdexcept_setround_387_prec_ctx (ctx, r | _FPU_EXTENDED);
+}
+
+static __always_inline void
+libc_feholdexcept_setround_387_53bit_ctx (struct rm_ctx *ctx, int r)
+{
+ libc_feholdexcept_setround_387_prec_ctx (ctx, r | _FPU_DOUBLE);
+}
+
+static __always_inline void
+libc_feholdsetround_387_prec_ctx (struct rm_ctx *ctx, int r)
+{
+ fpu_control_t cw, new_cw;
+
+ _FPU_GETCW (cw);
+ new_cw = cw;
+ new_cw &= ~(_FPU_RC_ZERO | _FPU_EXTENDED);
+ new_cw |= r;
+
+ ctx->env.__control_word = cw;
+ if (__glibc_unlikely (new_cw != cw))
+ {
+ _FPU_SETCW (new_cw);
+ ctx->updated_status = true;
+ }
+ else
+ ctx->updated_status = false;
+}
+
+static __always_inline void
+libc_feholdsetround_387_ctx (struct rm_ctx *ctx, int r)
+{
+ libc_feholdsetround_387_prec_ctx (ctx, r | _FPU_EXTENDED);
+}
+
+static __always_inline void
+libc_feholdsetround_387_53bit_ctx (struct rm_ctx *ctx, int r)
+{
+ libc_feholdsetround_387_prec_ctx (ctx, r | _FPU_DOUBLE);
+}
+
+static __always_inline void
+libc_feholdsetround_sse_ctx (struct rm_ctx *ctx, int r)
+{
+ unsigned int mxcsr, new_mxcsr;
+
+ asm (STMXCSR " %0" : "=m" (*&mxcsr));
+ new_mxcsr = (mxcsr & ~0x6000) | (r << 3);
+
+ ctx->env.__mxcsr = mxcsr;
+ if (__glibc_unlikely (new_mxcsr != mxcsr))
+ {
+ asm volatile (LDMXCSR " %0" : : "m" (*&new_mxcsr));
+ ctx->updated_status = true;
+ }
+ else
+ ctx->updated_status = false;
+}
+
+static __always_inline void
+libc_feresetround_sse_ctx (struct rm_ctx *ctx)
+{
+ if (__glibc_unlikely (ctx->updated_status))
+ libc_feresetround_sse (&ctx->env);
+}
+
+static __always_inline void
+libc_feresetround_387_ctx (struct rm_ctx *ctx)
+{
+ if (__glibc_unlikely (ctx->updated_status))
+ _FPU_SETCW (ctx->env.__control_word);
+}
+
+static __always_inline void
+libc_feupdateenv_387_ctx (struct rm_ctx *ctx)
+{
+ if (__glibc_unlikely (ctx->updated_status))
+ libc_feupdateenv_test_387 (&ctx->env, 0);
+}
+
+#ifdef __SSE_MATH__
+# define libc_feholdexcept_setroundf_ctx libc_feholdexcept_setround_sse_ctx
+# define libc_fesetenvf_ctx libc_fesetenv_sse_ctx
+# define libc_feupdateenvf_ctx libc_feupdateenv_sse_ctx
+# define libc_feholdsetroundf_ctx libc_feholdsetround_sse_ctx
+# define libc_feresetroundf_ctx libc_feresetround_sse_ctx
+#else
+# define libc_feholdexcept_setroundf_ctx libc_feholdexcept_setround_387_ctx
+# define libc_feupdateenvf_ctx libc_feupdateenv_387_ctx
+# define libc_feholdsetroundf_ctx libc_feholdsetround_387_ctx
+# define libc_feresetroundf_ctx libc_feresetround_387_ctx
+#endif /* __SSE_MATH__ */
+
+#ifdef __SSE2_MATH__
+# define libc_feholdexcept_setround_ctx libc_feholdexcept_setround_sse_ctx
+# define libc_fesetenv_ctx libc_fesetenv_sse_ctx
+# define libc_feupdateenv_ctx libc_feupdateenv_sse_ctx
+# define libc_feholdsetround_ctx libc_feholdsetround_sse_ctx
+# define libc_feresetround_ctx libc_feresetround_sse_ctx
+#else
+# define libc_feholdexcept_setround_ctx libc_feholdexcept_setround_387_ctx
+# define libc_feupdateenv_ctx libc_feupdateenv_387_ctx
+# define libc_feresetround_ctx libc_feresetround_387_ctx
+#endif /* __SSE2_MATH__ */
+
+#define libc_feholdexcept_setroundl_ctx libc_feholdexcept_setround_387_ctx
+#define libc_feupdateenvl_ctx libc_feupdateenv_387_ctx
+#define libc_feholdsetroundl_ctx libc_feholdsetround_387_ctx
+#define libc_feresetroundl_ctx libc_feresetround_387_ctx
+
+#ifndef __SSE2_MATH__
+# define libc_feholdsetround_53bit_ctx libc_feholdsetround_387_53bit_ctx
+# define libc_feresetround_53bit_ctx libc_feresetround_387_ctx
+#endif
+
#undef __mxcsr
#endif /* FENV_PRIVATE_H */