Make common fdim implementation generic.

The only difference is the usage of math_narrow_eval when
building s_fdiml.c.  This should be harmless for long double,
but I did observe some code generation changes on m68k, but
lack the resources to test it.

Likewise, to more easily support overriding symbol generation,
the aliasing macros are always conditionally defined on their
absence to reduce boilerplate.

I also ran builds for i486, ppc64, sparcv9, aarch64,
s390x and observed no changes to s_fdim* objects.

9 files changed, 19 insertions, 16 deletions

diff --git a/sysdeps/generic/math-type-macros-double.h b/sysdeps/generic/math-type-macros-double.h
index 4149b39a9b..154f416a7f 100644
--- a/sysdeps/generic/math-type-macros-double.h
+++ b/sysdeps/generic/math-type-macros-double.h
@@ -29,12 +29,12 @@
 /* Machines without a distinct long double type
    alias long double functions to their double
    equivalent.  */
-#if defined NO_LONG_DOUBLE
+#if defined NO_LONG_DOUBLE && !defined declare_mgen_alias
 # define declare_mgen_alias(from, to)	    \
    weak_alias (from, to)		    \
    strong_alias (from, from ## l)	    \
    weak_alias (from, to ## l)
-#else
+#elif !defined declare_mgen_alias
 # define declare_mgen_alias(from, to)	    \
    weak_alias (M_SUF (from), M_SUF (to))
 #endif
diff --git a/sysdeps/ieee754/ldbl-opt/math-type-macros-double.h b/sysdeps/ieee754/ldbl-opt/math-type-macros-double.h
index 8cb569454e..e78a5e3589 100644
--- a/sysdeps/ieee754/ldbl-opt/math-type-macros-double.h
+++ b/sysdeps/ieee754/ldbl-opt/math-type-macros-double.h
@@ -44,15 +44,20 @@
 #define LDOUBLE_cpowl_libm_version GLIBC_2_1
 #define LDOUBLE_clog10l_libm_version GLIBC_2_1
 #define LDOUBLE___clog10l_libm_version GLIBC_2_1
+#define LDOUBLE_fdiml_libm_version GLIBC_2_1
 
 /* Define compat symbols for long double on platforms
    where it was not always a distinct type.  */
-#define M_LIBM_NEED_COMPAT(f) \
+#if !defined M_LIBM_NEED_COMPAT
+# define M_LIBM_NEED_COMPAT(f) \
   LONG_DOUBLE_COMPAT (libm, LDOUBLE_ ## f ## l_libm_version)
+#endif
 
-#define declare_mgen_libm_compat(from, to)	      \
+#if !defined declare_mgen_libm_compat
+# define declare_mgen_libm_compat(from, to)	      \
   compat_symbol (libm, from, to ## l,		      \
 		 LDOUBLE_ ## to ## l_libm_version);
+#endif
 
 #include_next <math-type-macros-double.h>
 #endif
diff --git a/sysdeps/ieee754/ldbl-opt/math-type-macros-ldouble.h b/sysdeps/ieee754/ldbl-opt/math-type-macros-ldouble.h
index d2af4bbcc0..ae3713d49d 100644
--- a/sysdeps/ieee754/ldbl-opt/math-type-macros-ldouble.h
+++ b/sysdeps/ieee754/ldbl-opt/math-type-macros-ldouble.h
@@ -22,8 +22,10 @@
 
 /* Use properly versioned symbols for long double on platforms where
    it was not always a distinct type.  */
-#define declare_mgen_alias(from, to) \
+#if !defined declare_mgen_alias
+# define declare_mgen_alias(from, to) \
   long_double_symbol (libm, from ## l, to ## l);
+#endif
 
 #include_next <math-type-macros-ldouble.h>
 #endif
diff --git a/sysdeps/ieee754/ldbl-opt/s_fdim.c b/sysdeps/ieee754/ldbl-opt/s_fdim.c
deleted file mode 100644
index 02c95bfa81..0000000000
--- a/sysdeps/ieee754/ldbl-opt/s_fdim.c
+++ /dev/null
@@ -1,5 +0,0 @@
-#include <math_ldbl_opt.h>
-#include <math/s_fdim.c>
-#if LONG_DOUBLE_COMPAT(libm, GLIBC_2_1)
-compat_symbol (libm, __fdim, fdiml, GLIBC_2_1);
-#endif
diff --git a/sysdeps/ieee754/ldbl-opt/s_fdiml.c b/sysdeps/ieee754/ldbl-opt/s_fdiml.c
deleted file mode 100644
index 06b760b7b4..0000000000
--- a/sysdeps/ieee754/ldbl-opt/s_fdiml.c
+++ /dev/null
@@ -1,5 +0,0 @@
-#include <math_ldbl_opt.h>
-#undef weak_alias
-#define weak_alias(n,a)
-#include <math/s_fdiml.c>
-long_double_symbol (libm, __fdiml, fdiml);
diff --git a/sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdim-vis3.c b/sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdim-vis3.c
index 2973b49ffb..61765173b7 100644
--- a/sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdim-vis3.c
+++ b/sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdim-vis3.c
@@ -19,5 +19,7 @@
 #include <math.h>
 
 #define __fdim __fdim_vis3
+#define declare_mgen_alias(t, f)
+#define M_LIBM_NEED_COMPAT(f) 0
 
 #include <math/s_fdim.c>
diff --git a/sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdim.c b/sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdim.c
index 9666741fd1..2d07f312b4 100644
--- a/sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdim.c
+++ b/sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdim.c
@@ -27,6 +27,7 @@ sparc_libm_ifunc(__fdim, hwcap & HWCAP_SPARC_VIS3 ? __fdim_vis3 : __fdim_generic
 weak_alias (__fdim, fdim)
 
 # define __fdim __fdim_generic
+# define declare_mgen_alias(t, f)
 #endif
 
-#include <ldbl-opt/s_fdim.c>
+#include <math/s_fdim.c>
diff --git a/sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdimf-vis3.c b/sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdimf-vis3.c
index 75997c62d7..3f35b0dbff 100644
--- a/sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdimf-vis3.c
+++ b/sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdimf-vis3.c
@@ -19,5 +19,6 @@
 #include <math.h>
 
 #define __fdimf __fdimf_vis3
+#define declare_mgen_alias(t, f)
 
 #include <math/s_fdimf.c>
diff --git a/sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdimf.c b/sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdimf.c
index 767520fb18..b9add1c355 100644
--- a/sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdimf.c
+++ b/sysdeps/sparc/sparc32/sparcv9/fpu/multiarch/s_fdimf.c
@@ -27,6 +27,8 @@ sparc_libm_ifunc(__fdimf, hwcap & HWCAP_SPARC_VIS3 ? __fdimf_vis3 : __fdimf_gene
 weak_alias (__fdimf, fdimf)
 
 # define __fdimf __fdimf_generic
+# define declare_mgen_alias(t, f)
+
 #endif
 
 #include <math/s_fdimf.c>