glibc/sysdeps/ieee754/ldbl-128/s_compat_fromfpl.c

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Add fromfp functions. TS 18661-1 defines fromfp functions (fromfp, fromfpx, ufromfp, ufromfpx, and float and long double variants) to convert from floating-point to an integer type with any signedness and any given width up to that of intmax_t, in any of the five IEEE rounding modes (the usual four for binary floating point, plus rounding to nearest with ties rounding away from zero), with control of whether in-range non-integer values should result in the "inexact" exception being raised. This patch implements these functions for glibc. These implementations are (apart from raising exceptions) pure integer implementations; it's entirely possible optimized versions could be devised for some architectures. A common math/fromfp.h header provides various common helper code that can readily be shared between the implementations for different types. For each type, the bulk of the implementation is also shared between the four functions, with wrappers that define UNSIGNED and INEXACT macros appropriately before including the main implementation. As the functions return intmax_t and uintmax_t without math.h being allowed to expose those typedef names, they are declared using __intmax_t and __uintmax_t as obtained from <bits/types.h>. The FP_INT_* rounding direction macros are defined as ascending integers in the order the names are listed in the TS; I see no significant value in allowing architectures to vary the values of them. The libm-test machinery is duly adapted to handle unsigned int arguments, and intmax_t and uintmax_t results. Because each test input is generally tested for four functions, five rounding modes and several different widths, the libm-test.inc additions are very large. Thus, the diffs in the body of this message exclude the libm-test.inc changes, with the full patch being attached gzipped. The bulk of the new tests were generated (expanded from a test input plus rounding results and information about where it lies in the relevant interval between integers, to libm-test tests for all relevant combinations of function, rounding direction and width) by a script that's included in the patch as math/gen-fromfp-tests.py (input data math/gen-fromfp-tests-inputs); as an ad hoc script that's not really expected to be rerun, it's not very polished, but it's at least plausibly useful for adding any further tests for these functions in future. I may split the libm-test tests up by function in future (so both libm-test.inc and auto-libm-test-out are split into separate files, and the tests for each function are also built and run separately), but not for 2.25. For no obvious reason, adding tgmath tests for the new functions resulted in -Wuninitialized errors from test-tgmath.c about the variable i being used uninitialized. Those errors were correct - the variable is read by the frexp version in test-tgmath.c (where real frexp would write through that pointer instead of reading it) - but I don't know why this patch would result in the pre-existing issue being newly detected. The patch initializes the variable to avoid those errors. With these changes, glibc 2.25 should have all the library features from TS 18661-1 other than the functions that round result to narrower type (and constant rounding directions, but I'm considering those mainly a compiler feature not a library one). Tested for x86_64, x86, mips64 and powerpc. * math/bits/mathcalls.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (fromfp): New declaration. [__GLIBC_USE (IEC_60559_BFP_EXT)] (fromfpx): Likewise. [__GLIBC_USE (IEC_60559_BFP_EXT)] (ufromfp): Likewise. [__GLIBC_USE (IEC_60559_BFP_EXT)] (ufromfpx): Likewise. * math/tgmath.h (__TGMATH_TERNARY_FIRST_REAL_RET_ONLY): New macro. [__GLIBC_USE (IEC_60559_BFP_EXT)] (fromfp): Likewise. [__GLIBC_USE (IEC_60559_BFP_EXT)] (ufromfp): Likewise. [__GLIBC_USE (IEC_60559_BFP_EXT)] (fromfpx): Likewise. [__GLIBC_USE (IEC_60559_BFP_EXT)] (ufromfpx): Likewise. * math/math.h: Include <bits/types.h>. [__GLIBC_USE (IEC_60559_BFP_EXT)] (FP_INT_UPWARD): New enum constant and macro. (FP_INT_DOWNWARD): Likewise. (FP_INT_TOWARDZERO): Likewise. (FP_INT_TONEARESTFROMZERO): Likewise. (FP_INT_TONEAREST): Likewise. * math/Versions (fromfp): New libm symbol at version GLIBC_2.25. (fromfpf): Likewise. (fromfpl): Likewise. (ufromfp): Likewise. (ufromfpf): Likewise. (ufromfpl): Likewise. (fromfpx): Likewise. (fromfpxf): Likewise. (fromfpxl): Likewise. (ufromfpx): Likewise. (ufromfpxf): Likewise. (ufromfpxl): Likewise. * math/Makefile (libm-calls): Add s_fromfpF, s_ufromfpF, s_fromfpxF and s_ufromfpxF. * math/gen-fromfp-tests.py: New file. * math/gen-fromfp-tests-inputs: Likewise. * math/libm-test.inc: Include <stdint.h> (check_intmax_t): New function. (check_uintmax_t): Likewise. (struct test_fiu_M_data): New type. (struct test_fiu_U_data): Likewise. (RUN_TEST_fiu_M): New macro. (RUN_TEST_LOOP_fiu_M): Likewise. (RUN_TEST_fiu_U): Likewise. (RUN_TEST_LOOP_fiu_U): Likewise. (fromfp_test_data): New array. (fromfp_test): New function. (fromfpx_test_data): New array. (fromfpx_test): New function. (ufromfp_test_data): New array. (ufromfp_test): New function. (ufromfpx_test_data): New array. (ufromfpx_test): New function. (main): Call fromfp_test, fromfpx_test, ufromfp_test and ufromfpx_test. * math/gen-libm-test.pl (parse_args): Handle u, M and U descriptor characters. * math/test-tgmath-ret.c: Include <stdint.h>. (rm): New variable. (width): Likewise. (CHECK_RET_CONST_TYPE): Take extra arguments and pass them to called function. (CHECK_RET_CONST_FLOAT): Take extra arguments and pass them to CHECK_RET_CONST_TYPE. (CHECK_RET_CONST_DOUBLE): Likewise. (CHECK_RET_CONST_LDOUBLE): Likewise. (CHECK_RET_CONST): Take extra arguments and pass them to calls macros. (fromfp): New CHECK_RET_CONST call. (ufromfp): Likewise. (fromfpx): Likewise. (ufromfpx): Likewise. (do_test): Call check_return_fromfp, check_return_ufromfp, check_return_fromfpx and check_return_ufromfpx. * math/test-tgmath.c: Include <stdint.h> (NCALLS): Increase to 138. (F(compile_test)): Initialize i. Call fromfp functions. (F(fromfp)): New function. (F(fromfpx)): Likewise. (F(ufromfp)): Likewise. (F(ufromfpx)): Likewise. * manual/arith.texi (Rounding Functions): Document FP_INT_UPWARD, FP_INT_DOWNWARD, FP_INT_TOWARDZERO, FP_INT_TONEARESTFROMZERO, FP_INT_TONEAREST, fromfp, fromfpf, fromfpl, ufromfp, ufromfpf, ufromfpl, fromfpx, fromfpxf, fromfpxl, ufromfpx, ufromfpxf and ufromfpxl. * manual/libm-err-tab.pl (@all_functions): Add fromfp, fromfpx, ufromfp and ufromfpx. * math/fromfp.h: New file. * sysdeps/ieee754/dbl-64/s_fromfp.c: Likewise. * sysdeps/ieee754/dbl-64/s_fromfp_main.c: Likewise. * sysdeps/ieee754/dbl-64/s_fromfpx.c: Likewise. * sysdeps/ieee754/dbl-64/s_ufromfp.c: Likewise. * sysdeps/ieee754/dbl-64/s_ufromfpx.c: Likewise. * sysdeps/ieee754/flt-32/s_fromfpf.c: Likewise. * sysdeps/ieee754/flt-32/s_fromfpf_main.c: Likewise. * sysdeps/ieee754/flt-32/s_fromfpxf.c: Likewise. * sysdeps/ieee754/flt-32/s_ufromfpf.c: Likewise. * sysdeps/ieee754/flt-32/s_ufromfpxf.c: Likewise. * sysdeps/ieee754/ldbl-128/s_fromfpl.c: Likewise. * sysdeps/ieee754/ldbl-128/s_fromfpl_main.c: Likewise. * sysdeps/ieee754/ldbl-128/s_fromfpxl.c: Likewise. * sysdeps/ieee754/ldbl-128/s_ufromfpl.c: Likewise. * sysdeps/ieee754/ldbl-128/s_ufromfpxl.c: Likewise. * sysdeps/ieee754/ldbl-128ibm/s_fromfpl.c: Likewise. * sysdeps/ieee754/ldbl-128ibm/s_fromfpl_main.c: Likewise. * sysdeps/ieee754/ldbl-128ibm/s_fromfpxl.c: Likewise. * sysdeps/ieee754/ldbl-128ibm/s_ufromfpl.c: Likewise. * sysdeps/ieee754/ldbl-128ibm/s_ufromfpxl.c: Likewise. * sysdeps/ieee754/ldbl-96/s_fromfpl.c: Likewise. * sysdeps/ieee754/ldbl-96/s_fromfpl_main.c: Likewise. * sysdeps/ieee754/ldbl-96/s_fromfpxl.c: Likewise. * sysdeps/ieee754/ldbl-96/s_ufromfpl.c: Likewise. * sysdeps/ieee754/ldbl-96/s_ufromfpxl.c: Likewise. * sysdeps/ieee754/ldbl-opt/Makefile (libnldbl-calls): Add fromfp, ufromfp, fromfpx and ufromfpx. (CFLAGS-nldbl-fromfp.c): New variable. (CFLAGS-nldbl-fromfpx.c): Likewise. (CFLAGS-nldbl-ufromfp.c): Likewise. (CFLAGS-nldbl-ufromfpx.c): Likewise. * sysdeps/ieee754/ldbl-opt/nldbl-compat.h: Include <stdint.h>. * sysdeps/ieee754/ldbl-opt/nldbl-fromfp.c: New file. * sysdeps/ieee754/ldbl-opt/nldbl-fromfpx.c: Likewise. * sysdeps/ieee754/ldbl-opt/nldbl-ufromfp.c: Likewise. * sysdeps/ieee754/ldbl-opt/nldbl-ufromfpx.c: Likewise. * 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.
2016-12-31 00:40:59 +00:00
#define UNSIGNED 0
#define INEXACT 0
Change fromfp functions to return floating types following C23 (bug 28327) As discussed in bug 28327, C23 changed the fromfp functions to return floating types instead of intmax_t / uintmax_t. (Although the motivation in N2548 was reducing the use of intmax_t in library interfaces, the new version does have the advantage of being able to specify arbitrary integer widths for e.g. assigning the result to a _BitInt, as well as being able to indicate an error case in-band with a NaN return.) As with other such changes from interfaces introduced in TS 18661, implement the new types as a replacement for the old ones, with the old functions remaining as compat symbols but not supported as an API. The test generator used for many of the tests is updated to handle both versions of the functions. Tested for x86_64 and x86, and with build-many-glibcs.py. Also tested tgmath tests for x86_64 with GCC 7 to make sure that the modified case for older compilers in <tgmath.h> does work. Also tested for powerpc64le to cover the ldbl-128ibm implementation and the other things that are handled differently for that configuration. The new tests fail for ibm128, but all the failures relate to incorrect signs of zero results and turn out to arise from bugs in the underlying roundl, ceill, truncl and floorl implementations that I've reported in bug 33623, rather than indicating any bug in the actual new implementation of the functions for that format. So given fixes for those functions (which shouldn't be hard, and of course should add to the tests for those functions rather than relying only on indirect testing via fromfp), the fromfp tests should start passing for ibm128 as well.
2025-11-13 00:04:21 +00:00
#define FUNC __compat_fromfpl
Rename fromfp files in preparation for changing types for C23 As discussed in bug 28327, the fromfp functions changed type in C23 (compared to the version in TS 18661-1); they now return the same type as the floating-point argument, instead of intmax_t / uintmax_t. As with other such incompatible changes compared to the initial TS 18661 versions of interfaces (the types of totalorder functions, in particular), it seems appropriate to support only the new version as an API, not the old one (although many programs written for the old API might in fact work wtih the new one as well). Thus, the existing implementations should become compat symbols. They are sufficiently different from how I'd expect to implement the new version that using separate implementations in separate files is more convenient than trying to share code, and directly sharing testcases would be problematic as well. Rename the existing fromfp implementation and test files to names reflecting how they're intended to become compat symbols, so freeing up the existing filenames for a subsequent implementation of the C23 versions of these functions (which is the point at which the existing implementations would actually become compat symbols). gen-fromfp-tests.py and gen-fromfp-tests-inputs are not renamed; I think it will make sense to adapt the test generator to be able to generate most tests for both versions of the functions (with extra test inputs added that are only of interest with the C23 version). The ldbl-opt/nldbl-* files are also not renamed; since those are for a static only library, no compat versions are needed, and they'll just have their contents changed when the C23 version is implemented. Tested for x86_64, and with build-many-glibcs.py.
2025-11-04 23:41:35 +00:00
#include <s_compat_fromfpl_main.c>
Change fromfp functions to return floating types following C23 (bug 28327) As discussed in bug 28327, C23 changed the fromfp functions to return floating types instead of intmax_t / uintmax_t. (Although the motivation in N2548 was reducing the use of intmax_t in library interfaces, the new version does have the advantage of being able to specify arbitrary integer widths for e.g. assigning the result to a _BitInt, as well as being able to indicate an error case in-band with a NaN return.) As with other such changes from interfaces introduced in TS 18661, implement the new types as a replacement for the old ones, with the old functions remaining as compat symbols but not supported as an API. The test generator used for many of the tests is updated to handle both versions of the functions. Tested for x86_64 and x86, and with build-many-glibcs.py. Also tested tgmath tests for x86_64 with GCC 7 to make sure that the modified case for older compilers in <tgmath.h> does work. Also tested for powerpc64le to cover the ldbl-128ibm implementation and the other things that are handled differently for that configuration. The new tests fail for ibm128, but all the failures relate to incorrect signs of zero results and turn out to arise from bugs in the underlying roundl, ceill, truncl and floorl implementations that I've reported in bug 33623, rather than indicating any bug in the actual new implementation of the functions for that format. So given fixes for those functions (which shouldn't be hard, and of course should add to the tests for those functions rather than relying only on indirect testing via fromfp), the fromfp tests should start passing for ibm128 as well.
2025-11-13 00:04:21 +00:00
#if SHLIB_COMPAT (libm, GLIBC_2_25, GLIBC_2_43)
# define CONCATX(x, y) x ## y
# define CONCAT(x, y) CONCATX (x, y)
# define UNIQUE_ALIAS(name) CONCAT (name, __COUNTER__)
# define do_symbol(orig_name, name, aliasname) \
strong_alias (orig_name, name) \
compat_symbol (libm, name, aliasname, \
CONCAT (FIRST_VERSION_libm_, aliasname))
# undef weak_alias
# define weak_alias(name, aliasname) \
do_symbol (name, UNIQUE_ALIAS (name), aliasname);
libm_alias_ldouble (__compat_fromfp, fromfp)
#endif