This patch fixes bug 16315, bad pow handling of overflow/underflow in
non-default rounding modes. Tests of pow are duly converted to
ALL_RM_TEST to run all tests in all rounding modes.
There are two main issues here. First, various implementations
compute a negative result by negating a positive result, but this
yields inappropriate overflow / underflow values for directed
rounding, so either overflow / underflow results need recomputing in
the correct sign, or the relevant overflowing / underflowing operation
needs to be made to have a result of the correct sign. Second, the
dbl-64 implementation sets FE_TONEAREST internally; in the overflow /
underflow case, the result needs recomputing in the original rounding
mode.
Tested x86_64 and x86 and ulps updated accordingly.
[BZ #16315]
* sysdeps/i386/fpu/e_pow.S (__ieee754_pow): Ensure possibly
overflowing or underflowing operations take place with sign of
result.
* sysdeps/i386/fpu/e_powf.S (__ieee754_powf): Likewise.
* sysdeps/i386/fpu/e_powl.S (__ieee754_powl): Likewise.
* sysdeps/ieee754/dbl-64/e_pow.c: Include <math.h>.
(__ieee754_pow): Recompute overflowing and underflowing results in
original rounding mode.
* sysdeps/x86/fpu/powl_helper.c: Include <stdbool.h>.
(__powl_helper): Allow negative argument X and scale negated value
as needed. Avoid passing value outside [-1, 1] to f2xm1.
* sysdeps/x86_64/fpu/e_powl.S (__ieee754_powl): Ensure possibly
overflowing or underflowing operations take place with sign of
result.
* sysdeps/x86_64/fpu/multiarch/e_pow.c [HAVE_FMA4_SUPPORT]:
Include <math.h>.
* math/auto-libm-test-in: Add more tests of pow.
* math/auto-libm-test-out: Regenerated.
* math/libm-test.inc (pow_test): Use ALL_RM_TEST.
(pow_tonearest_test_data): Remove.
(pow_test_tonearest): Likewise.
(pow_towardzero_test_data): Likewise.
(pow_test_towardzero): Likewise.
(pow_downward_test_data): Likewise.
(pow_test_downward): Likewise.
(pow_upward_test_data): Likewise.
(pow_test_upward): Likewise.
(main): Don't call removed functions.
* sysdeps/i386/fpu/libm-test-ulps: Update.
* sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
This patch fixes bug 16064, i386 fenv_t not including SSE state, using
the technique suggested there of storing the state in the existing
__eip field of fenv_t to avoid needing to increase the size of fenv_t
and add new symbol versions. The included testcase, which previously
failed for i386 (but passed for x86_64), illustrates how the previous
state was buggy.
This patch causes the SSE state to be included *to the extent it is on
x86_64*. Where some state should logically be included but isn't for
x86_64 (see bug 16068), this patch does not cause it to be included
for i386 either. The idea is that any patch fixing that bug should
fix it for both x86_64 and i386 at once.
Tested i386 and x86_64. (I haven't tested the case of a CPU without
SSE2 disabling the test.)
[BZ #16064]
* sysdeps/i386/fpu/fegetenv.c: Include <unistd.h>, <ldsodefs.h>
and <dl-procinfo.h>.
(__fegetenv): Save SSE state in envp->__eip if supported.
* sysdeps/i386/fpu/feholdexcpt.c (feholdexcept): Save SSE state in
envp->__eip if supported.
* sysdeps/i386/fpu/fesetenv.c: Include <unistd.h>, <ldsodefs.h>
and <dl-procinfo.h>.
(__fesetenv): Always set __eip, __cs_selector, __opcode,
__data_offset and __data_selector in environment to 0. Set SSE
state if supported.
* sysdeps/x86/fpu/Makefile [$(subdir) = math] (tests): Add
test-fenv-sse.
[$(subdir) = math] (CFLAGS-test-fenv-sse.c): Add -msse2
-mfpmath=sse.
* sysdeps/x86/fpu/test-fenv-sse.c: New file.
When i386 and x86-64 mathinline.h was merged into a single mathinline.h,
"gcc -m32" enables x87 inline functions on x86-64 even when -mfpmath=sse
and SSE2 is enabled. It is a regression on x86-64. We should check
__SSE2_MATH__ instead of __x86_64__ when disabling x87 inline functions.