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58a813bf6e
GCC 4.9 and 5 do not generate a correct f{max,min}nm instruction for
__builtin_{fmax,fmin}{f} without -ffinite-math-only. It is clear a
compiler issue since the instruction can handle NaN and Inf correctly
and GCC6+ does not show this issue.
We can backport a fix to GCC 5, raise the minimum required GCC version
for aarch64 (since GCC 4.9 branch is now closed [1]) and/or add
configure check to check for this issue. However I think
-ffinite-math-only should be safe for these specific implementations
and it is a simpler solution.
Checked on aarch64-linux-gnu with GCC 5.3.1.
* sysdeps/aarch64/fpu/Makefile (CFLAGS-s_fmax.c, CFLAGS-s_fmaxf.c,
CFLAGS-s_fmin.c, CFLAGS-s_fminf.c): New rule: add -ffinite-math-only.
[1] https://gcc.gnu.org/ml/gcc/2016-08/msg00010.html
Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
15 lines
505 B
Makefile
15 lines
505 B
Makefile
ifeq ($(subdir),math)
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CFLAGS-e_sqrtf.c += -fno-math-errno
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CFLAGS-e_sqrt.c += -fno-math-errno
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CFLAGS-s_lroundf.c += -fno-math-errno
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CFLAGS-s_lround.c += -fno-math-errno
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CFLAGS-s_llroundf.c += -fno-math-errno
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CFLAGS-s_llround.c += -fno-math-errno
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# GCC 4.9 and 5 requires the flag to correct emits a f{max,min}nm
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# for a __builtin_{fmax,fmin}{f}.
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CFLAGS-s_fmax.c += -ffinite-math-only
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CFLAGS-s_fmaxf.c += -ffinite-math-only
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CFLAGS-s_fmin.c += -ffinite-math-only
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CFLAGS-s_fminf.c += -ffinite-math-only
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endif
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