Use floor functions not __floor functions in glibc libm.

Similar to the changes that were made to call sqrt functions directly
in glibc, instead of __ieee754_sqrt variants, so that the compiler
could inline them automatically without needing special inline
definitions in lots of math_private.h headers, this patch makes libm
code call floor functions directly instead of __floor variants,
removing the inlines / macros for x86_64 (SSE4.1) and powerpc
(POWER5).

The redirection used to ensure that __ieee754_sqrt does still get
called when the compiler doesn't inline a built-in function expansion
is refactored so it can be applied to other functions; the refactoring
is arranged so it's not limited to unary functions either (it would be
reasonable to use this mechanism for copysign - removing the inline in
math_private_calls.h but also eliminating unnecessary local PLT entry
use in the cases (powerpc soft-float and e500v1, for IBM long double)
where copysign calls don't get inlined).

The point of this change is that more architectures can get floor
calls inlined where they weren't previously (AArch64, for example),
without needing special inline definitions in their math_private.h,
and existing such definitions in math_private.h headers can be
removed.

Note that it's possible that in some cases an inline may be used where
an IFUNC call was previously used - this is the case on x86_64, for
example.  I think the direct calls to floor are still appropriate; if
there's any significant performance cost from inline SSE2 floor
instead of an IFUNC call ending up with SSE4.1 floor, that indicates
that either the function should be doing something else that's faster
than using floor at all, or it should itself have IFUNC variants, or
that the compiler choice of inlining for generic tuning should change
to allow for the possibility that, by not inlining, an SSE4.1 IFUNC
might be called at runtime - but not that glibc should avoid calling
floor internally.  (After all, all the same considerations would apply
to any user program calling floor, where it might either be inlined or
left as an out-of-line call allowing for a possible IFUNC.)

Tested for x86_64, and with build-many-glibcs.py.

	* include/math.h [!_ISOMAC && !(__FINITE_MATH_ONLY__ &&
	__FINITE_MATH_ONLY__ > 0) && !NO_MATH_REDIRECT] (MATH_REDIRECT):
	New macro.
	[!_ISOMAC && !(__FINITE_MATH_ONLY__ && __FINITE_MATH_ONLY__ > 0)
	&& !NO_MATH_REDIRECT] (MATH_REDIRECT_LDBL): Likewise.
	[!_ISOMAC && !(__FINITE_MATH_ONLY__ && __FINITE_MATH_ONLY__ > 0)
	&& !NO_MATH_REDIRECT] (MATH_REDIRECT_F128): Likewise.
	[!_ISOMAC && !(__FINITE_MATH_ONLY__ && __FINITE_MATH_ONLY__ > 0)
	&& !NO_MATH_REDIRECT] (MATH_REDIRECT_UNARY_ARGS): Likewise.
	[!_ISOMAC && !(__FINITE_MATH_ONLY__ && __FINITE_MATH_ONLY__ > 0)
	&& !NO_MATH_REDIRECT] (sqrt): Redirect using MATH_REDIRECT.
	[!_ISOMAC && !(__FINITE_MATH_ONLY__ && __FINITE_MATH_ONLY__ > 0)
	&& !NO_MATH_REDIRECT] (floor): Likewise.
	* sysdeps/aarch64/fpu/s_floor.c: Define NO_MATH_REDIRECT before
	header inclusion.
	* sysdeps/aarch64/fpu/s_floorf.c: Likewise.
	* sysdeps/ieee754/dbl-64/s_floor.c: Likewise.
	* sysdeps/ieee754/dbl-64/wordsize-64/s_floor.c: Likewise.
	* sysdeps/ieee754/float128/s_floorf128.c: Likewise.
	* sysdeps/ieee754/flt-32/s_floorf.c: Likewise.
	* sysdeps/ieee754/ldbl-128/s_floorl.c: Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_floorl.c: Likewise.
	* sysdeps/m68k/m680x0/fpu/s_floor_template.c: Likewise.
	* sysdeps/powerpc/powerpc32/power4/fpu/multiarch/s_floor.c: Likewise.
	* sysdeps/powerpc/powerpc32/power4/fpu/multiarch/s_floorf.c: Likewise.
	* sysdeps/powerpc/powerpc64/fpu/multiarch/s_floor.c: Likewise.
	* sysdeps/powerpc/powerpc64/fpu/multiarch/s_floorf.c: Likewise.
	* sysdeps/riscv/rv64/rvd/s_floor.c: Likewise.
	* sysdeps/riscv/rvf/s_floorf.c: Likewise.
	* sysdeps/sparc/sparc64/fpu/multiarch/s_floor.c: Likewise.
	* sysdeps/sparc/sparc64/fpu/multiarch/s_floorf.c: Likewise.
	* sysdeps/x86_64/fpu/multiarch/s_floor.c: Likewise.
	* sysdeps/x86_64/fpu/multiarch/s_floorf.c: Likewise.
	* sysdeps/powerpc/fpu/math_private.h [_ARCH_PWR5X] (__floor):
	Remove macro.
	[_ARCH_PWR5X] (__floorf): Likewise.
	* sysdeps/x86_64/fpu/math_private.h [__SSE4_1__] (__floor): Remove
	inline function.
	[__SSE4_1__] (__floorf): Likewise.
	* math/w_lgamma_main.c (LGFUNC (__lgamma)): Use floor functions
	instead of __floor variants.
	* math/w_lgamma_r_compat.c (__lgamma_r): Likewise.
	* math/w_lgammaf_main.c (LGFUNC (__lgammaf)): Likewise.
	* math/w_lgammaf_r_compat.c (__lgammaf_r): Likewise.
	* math/w_lgammal_main.c (LGFUNC (__lgammal)): Likewise.
	* math/w_lgammal_r_compat.c (__lgammal_r): Likewise.
	* math/w_tgamma_compat.c (__tgamma): Likewise.
	* math/w_tgamma_template.c (M_DECL_FUNC (__tgamma)): Likewise.
	* math/w_tgammaf_compat.c (__tgammaf): Likewise.
	* math/w_tgammal_compat.c (__tgammal): Likewise.
	* sysdeps/ieee754/dbl-64/e_lgamma_r.c (sin_pi): Likewise.
	* sysdeps/ieee754/dbl-64/k_rem_pio2.c (__kernel_rem_pio2):
	Likewise.
	* sysdeps/ieee754/dbl-64/lgamma_neg.c (__lgamma_neg): Likewise.
	* sysdeps/ieee754/flt-32/e_lgammaf_r.c (sin_pif): Likewise.
	* sysdeps/ieee754/flt-32/lgamma_negf.c (__lgamma_negf): Likewise.
	* sysdeps/ieee754/ldbl-128/e_lgammal_r.c (__ieee754_lgammal_r):
	Likewise.
	* sysdeps/ieee754/ldbl-128/e_powl.c (__ieee754_powl): Likewise.
	* sysdeps/ieee754/ldbl-128/lgamma_negl.c (__lgamma_negl):
	Likewise.
	* sysdeps/ieee754/ldbl-128/s_expm1l.c (__expm1l): Likewise.
	* sysdeps/ieee754/ldbl-128ibm/e_lgammal_r.c (__ieee754_lgammal_r):
	Likewise.
	* sysdeps/ieee754/ldbl-128ibm/e_powl.c (__ieee754_powl): Likewise.
	* sysdeps/ieee754/ldbl-128ibm/lgamma_negl.c (__lgamma_negl):
	Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_expm1l.c (__expm1l): Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_truncl.c (__truncl): Likewise.
	* sysdeps/ieee754/ldbl-96/e_lgammal_r.c (sin_pi): Likewise.
	* sysdeps/ieee754/ldbl-96/lgamma_negl.c (__lgamma_negl): Likewise.
	* sysdeps/powerpc/power5+/fpu/s_modf.c (__modf): Likewise.
	* sysdeps/powerpc/power5+/fpu/s_modff.c (__modff): Likewise.

1 files changed, 21 insertions, 8 deletions

diff --git a/include/math.h b/include/math.h
index 9ab7aa4403..eed953072b 100644
--- a/include/math.h
+++ b/include/math.h
@@ -79,16 +79,29 @@ fabsf128 (_Float128 x)
 
 # if !(defined __FINITE_MATH_ONLY__ && __FINITE_MATH_ONLY__ > 0)
 #  ifndef NO_MATH_REDIRECT
-/* Declare sqrt for use within GLIBC.  Compilers typically inline sqrt as a
-   single instruction.  Use an asm to avoid use of PLTs if it doesn't.  */
-float (sqrtf) (float) asm ("__ieee754_sqrtf");
-double (sqrt) (double) asm ("__ieee754_sqrt");
-#   ifndef __NO_LONG_DOUBLE_MATH
-long double (sqrtl) (long double) asm ("__ieee754_sqrtl");
+/* Declare some functions for use within GLIBC.  Compilers typically
+   inline those functions as a single instruction.  Use an asm to
+   avoid use of PLTs if it doesn't.  */
+#   define MATH_REDIRECT(FUNC, PREFIX, ARGS)			\
+  float (FUNC ## f) (ARGS (float)) asm (PREFIX #FUNC "f");	\
+  double (FUNC) (ARGS (double)) asm (PREFIX #FUNC );		\
+  MATH_REDIRECT_LDBL (FUNC, PREFIX, ARGS)			\
+  MATH_REDIRECT_F128 (FUNC, PREFIX, ARGS)
+#   ifdef __NO_LONG_DOUBLE_MATH
+#    define MATH_REDIRECT_LDBL(FUNC, PREFIX, ARGS)
+#   else
+#    define MATH_REDIRECT_LDBL(FUNC, PREFIX, ARGS)			\
+  long double (FUNC ## l) (ARGS (long double)) asm (PREFIX #FUNC "l");
 #   endif
-#   if __HAVE_DISTINCT_FLOAT128 > 0
-_Float128 (sqrtf128) (_Float128) asm ("__ieee754_sqrtf128");
+#   if __HAVE_DISTINCT_FLOAT128
+#    define MATH_REDIRECT_F128(FUNC, PREFIX, ARGS)			\
+  _Float128 (FUNC ## f128) (ARGS (_Float128)) asm (PREFIX #FUNC "f128");
+#   else
+#    define MATH_REDIRECT_F128(FUNC, PREFIX, ARGS)
 #   endif
+#   define MATH_REDIRECT_UNARY_ARGS(TYPE) TYPE
+MATH_REDIRECT (sqrt, "__ieee754_", MATH_REDIRECT_UNARY_ARGS)
+MATH_REDIRECT (floor, "__", MATH_REDIRECT_UNARY_ARGS)
 #  endif
 # endif