Add llogb, llogbf, llogbl.

TS 18661-1 defines llogb functions that are like ilogb except that
they return long int instead of int.  Corresponding FP_LLOGB* macros
are defined, whose values are required to have the obvious
correspondence to those of the FP_ILOGB* macros.

This patch implements these functions and macros for glibc.  llogb
uses the type-generic infrastructure, with an implementation similar
to the wrapper for ilogb but with additional conversion from FP_ILOGB*
to FP_LLOGB*; this approach avoids needing to modify or duplicate any
of the architecture-specific ilogb implementations.  Tests are also
based on those for ilogb.

Ideally the llogb functions would alias the ilogb ones when long is
32-bit, but such aliasing requires the associated header declarations
of the different-type alias to be hidden, typically by defining macros
before including the header (see e.g. how
sysdeps/ieee754/dbl-64/wordsize-64/s_llround.c defines lround to
__hidden_lround before including <math.h>).  The infrastructure for
type-generic function implementations does not support defining such
macros at present (since C code can't define a macro whose name is
determined by other macros).  So this patch leaves them as separate
functions (similar to e.g. scalbln and scalbn being separate in such a
case as well), but with the remapping of FP_ILOGB* to FP_LLOGB*
conditioned out in the case where it would be the identity map.

Tested for x86_64, x86, mips64 and powerpc.

	* math/bits/mathcalls.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (llogb):
	New declaration.
	* math/tgmath.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (llogb): New
	macro.
	* math/math.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (__FP_LONG_MAX):
	New macro.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FP_LLOGB0): Likewise.
	[__GLIBC_USE (IEC_60559_BFP_EXT)] (FP_LLOGBNAN): Likewise.
	* math/Versions (llogb): New libm symbol at version GLIBC_2.25.
	(llogbf): Likewise.
	(llogbl): Likewise.
	* math/Makefile (gen-libm-calls): Add w_llogbF.
	(tests): Add test-fp-llogb-constants.
	* math/w_llogb_template.c: New file.  Based on
	math/w_ilogb_template.c.
	* math/libm-test.inc (llogb_test_data): New array.
	(llogb_test): New function.
	(main): Call llogb_test.
	* math/test-fp-llogb-constants.c: New file.  Based on
	math/test-fp-ilogb-constants.c.
	* math/test-tgmath-ret.c (llogb): New CHECK_RET_CONST call.
	(do_test): Call check_return_llogb.
	* math/test-tgmath.c (NCALLS): Increase to 126.
	(F(compile_test)): Call llogb.
	(F(llogb)): New function.
	* manual/math.texi (Exponents and Logarithms): Document llogb,
	llogbf, llogbl, FP_LLOGB0 and FP_LLOGBNAN.
	* manual/libm-err-tab.pl (@all_functions): Add llogb.
	* sysdeps/ieee754/ldbl-opt/nldbl-llogb.c: New file.
	* sysdeps/ieee754/ldbl-opt/w_llogbl.c: Likewise.
	* sysdeps/ieee754/ldbl-opt/Makefile (libnldbl-calls): Add llogb.
	(CFLAGS-nldbl-llogb.c): New variable.
	* sysdeps/nacl/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/aarch64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/alpha/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/arm/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/hppa/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/i386/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/ia64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/microblaze/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips32/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/mips/mips64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/nios2/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/sh/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist:
	Likewise.
	* sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/64/libm.abilist: Likewise.
	* sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist: Likewise.

1 files changed, 11 insertions, 1 deletions

diff --git a/math/test-tgmath.c b/math/test-tgmath.c
index a919c64aab..be2c2fc3d4 100644
--- a/math/test-tgmath.c
+++ b/math/test-tgmath.c
@@ -50,7 +50,7 @@ int count_cdouble;
 int count_cfloat;
 int count_cldouble;
 
-#define NCALLS     125
+#define NCALLS     126
 #define NCALLS_INT 4
 #define NCCALLS    47
 
@@ -281,6 +281,7 @@ F(compile_test) (void)
   a = scalb (scalb (x, a), (TYPE) (6));
   k = scalbn (a, 7) + scalbln (c, 10l);
   i = ilogb (x);
+  j = llogb (x);
   a = fdim (fdim (x, a), fdim (c, b));
   b = fmax (fmax (a, x), fmax (c, b));
   a = fmin (fmin (x, a), fmin (c, b));
@@ -379,6 +380,7 @@ F(compile_test) (void)
       a = scalb (y, (const TYPE) (6));
       k = scalbn (y, 7) + scalbln (y, 10l);
       i = ilogb (y);
+      j = llogb (y);
       a = fdim (y, y);
       a = fmax (y, y);
       a = fmin (y, y);
@@ -846,6 +848,14 @@ int
   return x;
 }
 
+long int
+(F(llogb)) (TYPE x)
+{
+  ++count;
+  P ();
+  return x;
+}
+
 TYPE
 (F(fdim)) (TYPE x, TYPE y)
 {