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.
