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authorWilco Dijkstra <wdijkstr@arm.com>2015-09-18 16:30:43 +0100
committerWilco Dijkstra <wdijkstr@arm.com>2015-09-18 16:34:45 +0100
commit8df4e219e43a4a257d0759b54fef8c488e2f282e (patch)
treefd17e1976bc8fb5443476300f9bcf9645de920a9 /math/Makefile
parentcb2f668d4692df8d31b2ccf9b18b86bebe2d9174 (diff)
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Add inlining of the C99 math functions isinf/isnan/signbit/isfinite/isnormal/fpclassify using GCC
built-ins when available. Since going through the PLT is expensive for these small functions,
inlining results in major speedups (about 7x on Cortex-A57 for isinf). The GCC built-ins are not
correct if signalling NaN support is required, and thus are turned off in that case (see GCC bug
66462). The test-snan.c tests sNaNs and so must be explicitly built with -fsignaling-nans.

2015-09-18  Wilco Dijkstra  <wdijkstr@arm.com>

        [BZ #15367]
        [BZ #17441]

        * math/Makefile: Build test-snan.c with -fsignaling-nans.
        * math/math.h (fpclassify): Use __builtin_fpclassify when
        available.  (signbit): Use __builtin_signbit(f/l).
        (isfinite): Use__builtin_isfinite.  (isnormal): Use
        __builtin_isnormal.  (isnan): Use __builtin_isnan.
        (isinf): Use __builtin_isinf_sign.
Diffstat (limited to 'math/Makefile')
-rw-r--r--math/Makefile3
1 files changed, 2 insertions, 1 deletions
diff --git a/math/Makefile b/math/Makefile
index 48e7e4ce52..2e5291a378 100644
--- a/math/Makefile
+++ b/math/Makefile
@@ -176,6 +176,8 @@ CFLAGS-test-tgmath.c = -fno-builtin
 CFLAGS-test-tgmath2.c = -fno-builtin
 CFLAGS-test-tgmath-ret.c = -fno-builtin
 CFLAGS-test-powl.c = -fno-builtin
+
+CFLAGS-test-snan.c = -fsignaling-nans
 CPPFLAGS-test-ifloat.c = -U__LIBC_INTERNAL_MATH_INLINES \
 			 $(libm-test-fast-math-cflags)
 CPPFLAGS-test-idouble.c = -U__LIBC_INTERNAL_MATH_INLINES \
@@ -183,7 +185,6 @@ CPPFLAGS-test-idouble.c = -U__LIBC_INTERNAL_MATH_INLINES \
 CPPFLAGS-test-ildoubl.c = -U__LIBC_INTERNAL_MATH_INLINES \
 			  $(libm-test-fast-math-cflags)
 
-
 # The -lieee module sets the _LIB_VERSION_ switch to IEEE mode
 # for error handling in the -lm functions.
 install-lib += libieee.a