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author | Joseph Myers <joseph@codesourcery.com> | 2016-11-24 18:44:50 +0000 |
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committer | Joseph Myers <joseph@codesourcery.com> | 2016-11-24 18:44:50 +0000 |
commit | 93eb85ceb25ee7aff432ddea0abf559f53d7a5fc (patch) | |
tree | 7f3fa3024190dfadcda7c249e8b33e19e8b52128 /math/Makefile | |
parent | 380ec16d62f459d5a28cfc25b7b20990c45e1cc9 (diff) | |
download | glibc-93eb85ceb25ee7aff432ddea0abf559f53d7a5fc.zip glibc-93eb85ceb25ee7aff432ddea0abf559f53d7a5fc.tar.gz glibc-93eb85ceb25ee7aff432ddea0abf559f53d7a5fc.tar.bz2 |
Refactor float_t, double_t information into bits/flt-eval-method.h.
At present, definitions of float_t and double_t are split among many
bits/mathdef.h headers.
For all but three architectures, these types are float and double.
Furthermore, if you assume __FLT_EVAL_METHOD__ to be defined, that
provides a more generic way of determining the correct values of these
typedefs. Defining these typedefs more generally based on
__FLT_EVAL_METHOD__ was previously proposed by Paul Eggert in
<https://sourceware.org/ml/libc-alpha/2012-02/msg00002.html>.
This patch refactors things in the way I proposed in
<https://sourceware.org/ml/libc-alpha/2016-11/msg00745.html>. A new
header bits/flt-eval-method.h defines a single macro,
__GLIBC_FLT_EVAL_METHOD, which is then used by math.h to define
float_t and double_t. The default is based on __FLT_EVAL_METHOD__
(although actually a default to 0 would have the same effect for
current ports, because ports where values other than 0 or 16 are
possible all have their own headers).
To avoid changing the existing semantics in any case, including for
compilers not defining __FLT_EVAL_METHOD__, architecture-specific
files are then added for m68k, s390, x86 which replicate the existing
semantics. At least with __FLT_EVAL_METHOD__ values possible with
GCC, there should be no change to the choices of float_t and double_t
for any supported configuration.
Architecture maintainer notes:
* m68k: sysdeps/m68k/m680x0/bits/flt-eval-method.h always defines
__GLIBC_FLT_EVAL_METHOD to 2 to replicate the existing logic. But
actually GCC defines __FLT_EVAL_METHOD__ to 0 if TARGET_68040. It
might make sense to make the header prefer to base things on
__FLT_EVAL_METHOD__ if defined, like the x86 version, and so make
the choices of these types more accurate (with a NEWS entry as for
the other changes to these types on particular architectures).
* s390: sysdeps/s390/bits/flt-eval-method.h always defines
__GLIBC_FLT_EVAL_METHOD to 1 to replicate the existing logic. As
previously discussed, it might make sense in coordination with GCC
to eliminate the historic mistake, avoid excess precision in the
-fexcess-precision=standard case and make the typedefs match (with a
NEWS entry, again).
Tested for x86-64 and x86. Also did compilation-only testing with
build-many-glibcs.py.
* bits/flt-eval-method.h: New file.
* sysdeps/m68k/m680x0/bits/flt-eval-method.h: Likewise.
* sysdeps/s390/bits/flt-eval-method.h: Likewise.
* sysdeps/x86/bits/flt-eval-method.h: Likewise.
* math/Makefile (headers): Add bits/flt-eval-method.h.
* math/math.h: Include <bits/flt-eval-method.h>.
[__USE_ISOC99] (float_t): Define based on __GLIBC_FLT_EVAL_METHOD.
[__USE_ISOC99] (double_t): Likewise.
* bits/mathdef.h (float_t): Remove.
(double_t): Likewise.
* sysdeps/aarch64/bits/mathdef.h (float_t): Likewise.
(double_t): Likewise.
* sysdeps/alpha/bits/mathdef.h (float_t): Likewise.
(double_t): Likewise.
* sysdeps/arm/bits/mathdef.h (float_t): Likewise.
(double_t): Likewise.
* sysdeps/hppa/fpu/bits/mathdef.h (float_t): Likewise.
(double_t): Likewise.
* sysdeps/ia64/bits/mathdef.h (float_t): Likewise.
(double_t): Likewise.
* sysdeps/m68k/m680x0/bits/mathdef.h (float_t): Likewise.
(double_t): Likewise.
* sysdeps/mips/bits/mathdef.h (float_t): Likewise.
(double_t): Likewise.
* sysdeps/powerpc/bits/mathdef.h (float_t): Likewise.
(double_t): Likewise.
* sysdeps/s390/bits/mathdef.h (float_t): Likewise.
(double_t): Likewise.
* sysdeps/sh/sh4/bits/mathdef.h (float_t): Likewise.
(double_t): Likewise.
* sysdeps/sparc/bits/mathdef.h (float_t): Likewise.
(double_t): Likewise.
* sysdeps/tile/bits/mathdef.h (float_t): Likewise.
(double_t): Likewise.
* sysdeps/x86/bits/mathdef.h (float_t): Likewise.
(double_t): Likewise.
Diffstat (limited to 'math/Makefile')
-rw-r--r-- | math/Makefile | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/math/Makefile b/math/Makefile index e84f86a..576e108 100644 --- a/math/Makefile +++ b/math/Makefile @@ -27,7 +27,8 @@ headers := math.h bits/mathcalls.h bits/mathinline.h bits/huge_val.h \ fpu_control.h complex.h bits/cmathcalls.h fenv.h \ bits/fenv.h bits/fenvinline.h bits/mathdef.h tgmath.h \ bits/math-finite.h bits/math-vector.h \ - bits/libm-simd-decl-stubs.h bits/iscanonical.h + bits/libm-simd-decl-stubs.h bits/iscanonical.h \ + bits/flt-eval-method.h # FPU support code. aux := setfpucw fpu_control |