From: Wilco Dijkstra Date: Thu, 15 Mar 2018 17:57:03 +0000 (+0000) Subject: Add support for sqrt asm redirects X-Git-Tag: glibc-2.28~469 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=1294b1892e;p=thirdparty%2Fglibc.git Add support for sqrt asm redirects This patch series cleans up the many uses of __ieee754_sqrt(f/l) in GLIBC. The goal is to enable GCC to do the inlining, and if this fails call the __ieee754_sqrt function. This is done by internally declaring sqrt with asm redirects. The compat symbols and sqrt wrappers need to disable the redirect. The redirect is also disabled if there are already redirects defined when using -ffinite-math-only. All math functions (but not math tests, non-library code and libnldbl) are built with -fno-math-errno which means GCC will typically inline sqrt as a single instruction. This means targets are no longer forced to add a special inline for sqrt. * include/math.h (sqrt): Declare with asm redirect. (sqrtf): Likewise. (sqrtl): Likewise. (sqrtf128): Likewise. * Makeconfig: Add -fno-math-errno for libc/libm, but build testsuite, nonlib and libnldbl with -fmath-errno. * math/w_sqrt_compat.c: Define NO_MATH_REDIRECT. * math/w_sqrt_template.c: Likewise. * math/w_sqrtf_compat.c: Likewise. * math/w_sqrtl_compat.c: Likewise. * sysdeps/i386/fpu/w_sqrt.c: Likewise. * sysdeps/i386/fpu/w_sqrt_compat.c: Likewise. * sysdeps/generic/math-type-macros-float128.h: Remove math.h and complex.h. --- diff --git a/ChangeLog b/ChangeLog index 6c8c880243a..1a497eaa68e 100644 --- a/ChangeLog +++ b/ChangeLog @@ -25,6 +25,23 @@ [__USE_ISOC99] (llrintf): Likewise. [__USE_ISOC99] (llrintl): Likewise. +2018-03-15 Wilco Dijkstra + + * include/math.h (sqrt): Declare with asm redirect. + (sqrtf): Likewise. + (sqrtl): Likewise. + (sqrtf128): Likewise. + * Makeconfig: Add -fno-math-errno for libc/libm, but build testsuite, + nonlib and libnldbl with -fmath-errno. + * math/w_sqrt_compat.c: Define NO_MATH_REDIRECT. + * math/w_sqrt_template.c: Likewise. + * math/w_sqrtf_compat.c: Likewise. + * math/w_sqrtl_compat.c: Likewise. + * sysdeps/i386/fpu/w_sqrt.c: Likewise. + * sysdeps/i386/fpu/w_sqrt_compat.c: Likewise. + * sysdeps/generic/math-type-macros-float128.h: Remove math.h and + complex.h. + 2018-03-15 Wilco Dijkstra * benchtests/Makefile: Define _ISOMAC. diff --git a/Makeconfig b/Makeconfig index 86a71e58021..1afe86475c1 100644 --- a/Makeconfig +++ b/Makeconfig @@ -831,6 +831,9 @@ endif # disable any optimization that assume default rounding mode. +math-flags = -frounding-math +# Build libc/libm using -fno-math-errno, but run testsuite with -fmath-errno. ++extra-math-flags = $(if $(filter libnldbl nonlib testsuite,$(in-module)),-fmath-errno,-fno-math-errno) + # We might want to compile with some stack-protection flag. ifneq ($(stack-protector),) +stack-protector=$(stack-protector) @@ -966,6 +969,7 @@ endif override CFLAGS = -std=gnu11 -fgnu89-inline $(config-extra-cflags) \ $(filter-out %frame-pointer,$(+cflags)) $(+gccwarn-c) \ + $(+extra-math-flags) \ $(sysdep-CFLAGS) $(CFLAGS-$(suffix $@)) $(CFLAGS-$( 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"); +# endif +# if __HAVE_DISTINCT_FLOAT128 > 0 +_Float128 (sqrtf128) (_Float128) asm ("__ieee754_sqrtf128"); +# endif +# endif +# endif + #endif #endif diff --git a/math/w_sqrt_compat.c b/math/w_sqrt_compat.c index 7884d146331..e76a8079aa0 100644 --- a/math/w_sqrt_compat.c +++ b/math/w_sqrt_compat.c @@ -16,6 +16,7 @@ License along with the GNU C Library; if not, see . */ +#define NO_MATH_REDIRECT #include #include #include diff --git a/math/w_sqrt_template.c b/math/w_sqrt_template.c index 52a21c0bf1c..9c6ac75956c 100644 --- a/math/w_sqrt_template.c +++ b/math/w_sqrt_template.c @@ -21,6 +21,7 @@ for each floating-point type. */ #if __USE_WRAPPER_TEMPLATE +# define NO_MATH_REDIRECT # include # include # include diff --git a/math/w_sqrtf_compat.c b/math/w_sqrtf_compat.c index 824ce0ed465..cad9b4ad77f 100644 --- a/math/w_sqrtf_compat.c +++ b/math/w_sqrtf_compat.c @@ -16,6 +16,7 @@ License along with the GNU C Library; if not, see . */ +#define NO_MATH_REDIRECT #include #include #include diff --git a/math/w_sqrtl_compat.c b/math/w_sqrtl_compat.c index 56627a615dc..16dda403b77 100644 --- a/math/w_sqrtl_compat.c +++ b/math/w_sqrtl_compat.c @@ -16,6 +16,7 @@ License along with the GNU C Library; if not, see . */ +#define NO_MATH_REDIRECT #include #include #include diff --git a/sysdeps/generic/math-type-macros-float128.h b/sysdeps/generic/math-type-macros-float128.h index 605996e0ba7..485c13bb88a 100644 --- a/sysdeps/generic/math-type-macros-float128.h +++ b/sysdeps/generic/math-type-macros-float128.h @@ -19,9 +19,6 @@ #ifndef _MATH_TYPE_MACROS_FLOAT128 #define _MATH_TYPE_MACROS_FLOAT128 -#include -#include - #define M_LIT(c) __f128 (c) #define M_PFX FLT128 #define M_SUF(c) c ## f128 diff --git a/sysdeps/i386/fpu/w_sqrt.c b/sysdeps/i386/fpu/w_sqrt.c index d37a5d55bf4..8bef04e68a7 100644 --- a/sysdeps/i386/fpu/w_sqrt.c +++ b/sysdeps/i386/fpu/w_sqrt.c @@ -1,5 +1,6 @@ /* The inline __ieee754_sqrt is not correctly rounding; it's OK for most internal uses in glibc, but not for sqrt itself. */ +#define NO_MATH_REDIRECT #define __ieee754_sqrt __avoid_ieee754_sqrt #include #include diff --git a/sysdeps/i386/fpu/w_sqrt_compat.c b/sysdeps/i386/fpu/w_sqrt_compat.c index ddd36d0964c..dd485f4b88c 100644 --- a/sysdeps/i386/fpu/w_sqrt_compat.c +++ b/sysdeps/i386/fpu/w_sqrt_compat.c @@ -1,5 +1,6 @@ /* The inline __ieee754_sqrt is not correctly rounding; it's OK for most internal uses in glibc, but not for sqrt itself. */ +#define NO_MATH_REDIRECT #define __ieee754_sqrt __avoid_ieee754_sqrt #include #include