diff options
author | Alex Bennée <alex.bennee@linaro.org> | 2017-12-05 17:14:42 +0000 |
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committer | Alex Bennée <alex.bennee@linaro.org> | 2018-02-21 10:21:47 +0000 |
commit | 0c4c90929143a530730e2879204a55a30bf63758 (patch) | |
tree | 8de5fe0c925eccc2468a53a4e4ca4afff7467543 /fpu/softfloat.c | |
parent | 89360067071b1844bf745682e18db7dde74cdb8d (diff) |
fpu/softfloat: re-factor compare
The compare function was already expanded from a macro. I keep the
macro expansion but move most of the logic into a compare_decomposed.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Diffstat (limited to 'fpu/softfloat.c')
-rw-r--r-- | fpu/softfloat.c | 134 |
1 files changed, 80 insertions, 54 deletions
diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 7a53c36da4..4bc425d7e4 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -1783,6 +1783,86 @@ MINMAX(64, maxnummag, false, true, true) #undef MINMAX +/* Floating point compare */ +static int compare_floats(FloatParts a, FloatParts b, bool is_quiet, + float_status *s) +{ + if (is_nan(a.cls) || is_nan(b.cls)) { + if (!is_quiet || + a.cls == float_class_snan || + b.cls == float_class_snan) { + s->float_exception_flags |= float_flag_invalid; + } + return float_relation_unordered; + } + + if (a.cls == float_class_zero) { + if (b.cls == float_class_zero) { + return float_relation_equal; + } + return b.sign ? float_relation_greater : float_relation_less; + } else if (b.cls == float_class_zero) { + return a.sign ? float_relation_less : float_relation_greater; + } + + /* The only really important thing about infinity is its sign. If + * both are infinities the sign marks the smallest of the two. + */ + if (a.cls == float_class_inf) { + if ((b.cls == float_class_inf) && (a.sign == b.sign)) { + return float_relation_equal; + } + return a.sign ? float_relation_less : float_relation_greater; + } else if (b.cls == float_class_inf) { + return b.sign ? float_relation_greater : float_relation_less; + } + + if (a.sign != b.sign) { + return a.sign ? float_relation_less : float_relation_greater; + } + + if (a.exp == b.exp) { + if (a.frac == b.frac) { + return float_relation_equal; + } + if (a.sign) { + return a.frac > b.frac ? + float_relation_less : float_relation_greater; + } else { + return a.frac > b.frac ? + float_relation_greater : float_relation_less; + } + } else { + if (a.sign) { + return a.exp > b.exp ? float_relation_less : float_relation_greater; + } else { + return a.exp > b.exp ? float_relation_greater : float_relation_less; + } + } +} + +#define COMPARE(sz) \ +int float ## sz ## _compare(float ## sz a, float ## sz b, \ + float_status *s) \ +{ \ + FloatParts pa = float ## sz ## _unpack_canonical(a, s); \ + FloatParts pb = float ## sz ## _unpack_canonical(b, s); \ + return compare_floats(pa, pb, false, s); \ +} \ +int float ## sz ## _compare_quiet(float ## sz a, float ## sz b, \ + float_status *s) \ +{ \ + FloatParts pa = float ## sz ## _unpack_canonical(a, s); \ + FloatParts pb = float ## sz ## _unpack_canonical(b, s); \ + return compare_floats(pa, pb, true, s); \ +} + +COMPARE(16) +COMPARE(32) +COMPARE(64) + +#undef COMPARE + /* Multiply A by 2 raised to the power N. */ static FloatParts scalbn_decomposed(FloatParts a, int n, float_status *s) { @@ -6884,60 +6964,6 @@ int float128_unordered_quiet(float128 a, float128 b, float_status *status) return 0; } -#define COMPARE(s, nan_exp) \ -static inline int float ## s ## _compare_internal(float ## s a, float ## s b,\ - int is_quiet, float_status *status) \ -{ \ - flag aSign, bSign; \ - uint ## s ## _t av, bv; \ - a = float ## s ## _squash_input_denormal(a, status); \ - b = float ## s ## _squash_input_denormal(b, status); \ - \ - if (( ( extractFloat ## s ## Exp( a ) == nan_exp ) && \ - extractFloat ## s ## Frac( a ) ) || \ - ( ( extractFloat ## s ## Exp( b ) == nan_exp ) && \ - extractFloat ## s ## Frac( b ) )) { \ - if (!is_quiet || \ - float ## s ## _is_signaling_nan(a, status) || \ - float ## s ## _is_signaling_nan(b, status)) { \ - float_raise(float_flag_invalid, status); \ - } \ - return float_relation_unordered; \ - } \ - aSign = extractFloat ## s ## Sign( a ); \ - bSign = extractFloat ## s ## Sign( b ); \ - av = float ## s ## _val(a); \ - bv = float ## s ## _val(b); \ - if ( aSign != bSign ) { \ - if ( (uint ## s ## _t) ( ( av | bv )<<1 ) == 0 ) { \ - /* zero case */ \ - return float_relation_equal; \ - } else { \ - return 1 - (2 * aSign); \ - } \ - } else { \ - if (av == bv) { \ - return float_relation_equal; \ - } else { \ - return 1 - 2 * (aSign ^ ( av < bv )); \ - } \ - } \ -} \ - \ -int float ## s ## _compare(float ## s a, float ## s b, float_status *status) \ -{ \ - return float ## s ## _compare_internal(a, b, 0, status); \ -} \ - \ -int float ## s ## _compare_quiet(float ## s a, float ## s b, \ - float_status *status) \ -{ \ - return float ## s ## _compare_internal(a, b, 1, status); \ -} - -COMPARE(32, 0xff) -COMPARE(64, 0x7ff) - static inline int floatx80_compare_internal(floatx80 a, floatx80 b, int is_quiet, float_status *status) { |