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.

44 files changed, 398 insertions, 8 deletions

diff --git a/ChangeLog b/ChangeLog
index 7acf5caabb..62e49bb03a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,71 @@
+2016-12-02  Joseph Myers  <joseph@codesourcery.com>
+
+	* 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.
+
 2016-12-01  Joseph Myers  <joseph@codesourcery.com>
 
 	* sysdeps/ieee754/ldbl-128/s_getpayloadl.c (getpayloadl): Use
diff --git a/NEWS b/NEWS
index b2a0b0f1f8..c2e973d183 100644
--- a/NEWS
+++ b/NEWS
@@ -53,6 +53,9 @@ Version 2.25
 
   - Signaling NaN macros: SNANF, SNAN, SNANL.
 
+  - llogb functions: the llogb, llogbf and llogbl functions, and the
+    FP_LLOGB0 and FP_LLOGBNAN macros.
+
   - Comparison macros: iseqsig.
 
   - Classification macros: iscanonical, issubnormal, iszero.
diff --git a/manual/libm-err-tab.pl b/manual/libm-err-tab.pl
index 6d0bffc372..0e83853949 100755
--- a/manual/libm-err-tab.pl
+++ b/manual/libm-err-tab.pl
@@ -58,7 +58,7 @@ use vars qw (%results @all_floats %suffices @all_functions);
     "creal", "csin", "csinh", "csqrt", "ctan", "ctanh", "erf", "erfc",
     "exp", "exp10", "exp2", "expm1", "fabs", "fdim", "floor", "fma",
     "fmax", "fmin", "fmod", "frexp", "gamma", "hypot",
-    "ilogb", "j0", "j1", "jn", "lgamma", "lrint",
+    "ilogb", "j0", "j1", "jn", "lgamma", "llogb", "lrint",
     "llrint", "log", "log10", "log1p", "log2", "logb", "lround",
     "llround", "modf", "nearbyint", "nextafter", "nextdown", "nexttoward",
     "nextup", "pow", "remainder", "remquo", "rint", "round", "scalb",
diff --git a/manual/math.texi b/manual/math.texi
index b4bb32345e..5ad8732eca 100644
--- a/manual/math.texi
+++ b/manual/math.texi
@@ -584,9 +584,20 @@ negative), @code{logb} returns @math{@infinity{}}.  If @var{x} is zero,
 @comment math.h
 @comment ISO
 @deftypefunx int ilogbl (long double @var{x})
+@comment math.h
+@comment ISO
+@deftypefunx {long int} llogb (double @var{x})
+@comment math.h
+@comment ISO
+@deftypefunx {long int} llogbf (float @var{x})
+@comment math.h
+@comment ISO
+@deftypefunx {long int} llogbl (long double @var{x})
 @safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}}
 These functions are equivalent to the corresponding @code{logb}
-functions except that they return signed integer values.
+functions except that they return signed integer values.  The
+@code{ilogb} functions are from ISO C99; the @code{llogb} functions
+are from TS 18661-1:2014.
 @end deftypefun
 
 @noindent
@@ -605,6 +616,15 @@ This macro is defined in @w{ISO C99}.
 
 @comment math.h
 @comment ISO
+@deftypevr Macro {long int} FP_LLOGB0
+@code{llogb} returns this value if its argument is @code{0}.  The
+numeric value is either @code{LONG_MIN} or @code{-LONG_MAX}.
+
+This macro is defined in TS 18661-1:2014.
+@end deftypevr
+
+@comment math.h
+@comment ISO
 @deftypevr Macro int FP_ILOGBNAN
 @code{ilogb} returns this value if its argument is @code{NaN}.  The
 numeric value is either @code{INT_MIN} or @code{INT_MAX}.
@@ -612,6 +632,15 @@ numeric value is either @code{INT_MIN} or @code{INT_MAX}.
 This macro is defined in @w{ISO C99}.
 @end deftypevr
 
+@comment math.h
+@comment ISO
+@deftypevr Macro {long int} FP_LLOGBNAN
+@code{llogb} returns this value if its argument is @code{NaN}.  The
+numeric value is either @code{LONG_MIN} or @code{LONG_MAX}.
+
+This macro is defined in TS 18661-1:2014.
+@end deftypevr
+
 These values are system specific.  They might even be the same.  The
 proper way to test the result of @code{ilogb} is as follows:
 
diff --git a/math/Makefile b/math/Makefile
index ac3a90a582..848b093863 100644
--- a/math/Makefile
+++ b/math/Makefile
@@ -52,7 +52,7 @@ gen-libm-calls = cargF conjF cimagF crealF cabsF s_cacosF		  \
 		 k_casinhF s_csinhF k_casinhF s_csinhF s_catanhF s_catanF \
 		 s_ctanF s_ctanhF s_cexpF s_clogF s_cprojF s_csqrtF	  \
 		 s_cpowF s_clog10F s_fdimF s_nextdownF s_fmaxF s_fminF	  \
-		 s_nanF s_iseqsigF s_canonicalizeF w_ilogbF
+		 s_nanF s_iseqsigF s_canonicalizeF w_ilogbF w_llogbF
 
 libm-calls =								  \
 	e_acosF e_acoshF e_asinF e_atan2F e_atanhF e_coshF e_expF e_fmodF \
@@ -159,7 +159,7 @@ tests = test-matherr test-fenv atest-exp atest-sincos atest-exp2 basic-test \
 	test-fesetexcept-traps test-fetestexceptflag test-femode \
 	test-femode-traps test-iszero-excess-precision \
 	test-iseqsig-excess-precision test-flt-eval-method \
-	test-fp-ilogb-constants $(tests-static)
+	test-fp-ilogb-constants test-fp-llogb-constants $(tests-static)
 tests-static = test-fpucw-static test-fpucw-ieee-static \
 	       test-signgam-uchar-static test-signgam-uchar-init-static \
 	       test-signgam-uint-static test-signgam-uint-init-static \
diff --git a/math/Versions b/math/Versions
index 143e53f052..6fe9bb7e6f 100644
--- a/math/Versions
+++ b/math/Versions
@@ -223,5 +223,6 @@ libm {
     canonicalize; canonicalizef; canonicalizel;
     setpayload; setpayloadf; setpayloadl;
     setpayloadsig; setpayloadsigf; setpayloadsigl;
+    llogb; llogbf; llogbl;
   }
 }
diff --git a/math/bits/mathcalls.h b/math/bits/mathcalls.h
index 54ea4b8f30..c57b5627cd 100644
--- a/math/bits/mathcalls.h
+++ b/math/bits/mathcalls.h
@@ -315,6 +315,11 @@ __MATHCALL (scalbn,, (_Mdouble_ __x, int __n));
 __MATHDECL (int,ilogb,, (_Mdouble_ __x));
 #endif
 
+#if __GLIBC_USE (IEC_60559_BFP_EXT)
+/* Like ilogb, but returning long int.  */
+__MATHDECL (long int, llogb,, (_Mdouble_ __x));
+#endif
+
 #ifdef __USE_ISOC99
 /* Return X times (2 to the Nth power).  */
 __MATHCALL (scalbln,, (_Mdouble_ __x, long int __n));
diff --git a/math/libm-test.inc b/math/libm-test.inc
index 81d114b04f..85df9deb86 100644
--- a/math/libm-test.inc
+++ b/math/libm-test.inc
@@ -50,7 +50,7 @@
    ilogb, iscanonical, isfinite, isinf, isnan, isnormal, issignaling,
    issubnormal, iszero, iseqsig, isless, islessequal, isgreater,
    isgreaterequal, islessgreater, isunordered, j0, j1, jn,
-   ldexp, lgamma, log, log10, log1p, log2, logb,
+   ldexp, lgamma, llogb, log, log10, log1p, log2, logb,
    modf, nearbyint, nextafter, nexttoward,
    pow, pow10, remainder, remquo, rint, lrint, llrint,
    round, lround, llround,
@@ -9171,6 +9171,48 @@ gamma_test (void)
 }
 
 
+static const struct test_f_l_data llogb_test_data[] =
+  {
+    TEST_f_l (llogb, 1, 0, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_l (llogb, lit_e, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_l (llogb, 1024, 10, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_l (llogb, -2000, 10, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_l (llogb, 0.5, -1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED);
+    TEST_f_l (llogb, -0.5, -1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED);
+
+#if MANT_DIG >= 57
+    TEST_f_l (llogb, 0x1.ffffffffffffffp1L, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+    TEST_f_l (llogb, -0x1.ffffffffffffffp1L, 1, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED),
+#endif
+
+    TEST_f_l (llogb, min_subnorm_value, MIN_EXP-MANT_DIG, NO_INEXACT_EXCEPTION|ERRNO_UNCHANGED);
+