From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35770) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ej6Wb-0007BG-Dz for qemu-devel@nongnu.org; Tue, 06 Feb 2018 11:55:18 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ej6WZ-0001ah-3I for qemu-devel@nongnu.org; Tue, 06 Feb 2018 11:55:17 -0500 Received: from mail-wr0-x244.google.com ([2a00:1450:400c:c0c::244]:41108) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1ej6WY-0001Yl-EL for qemu-devel@nongnu.org; Tue, 06 Feb 2018 11:55:15 -0500 Received: by mail-wr0-x244.google.com with SMTP id v15so2673786wrb.8 for ; Tue, 06 Feb 2018 08:55:14 -0800 (PST) From: =?UTF-8?q?Alex=20Benn=C3=A9e?= Date: Tue, 6 Feb 2018 16:48:14 +0000 Message-Id: <20180206164815.10084-22-alex.bennee@linaro.org> In-Reply-To: <20180206164815.10084-1-alex.bennee@linaro.org> References: <20180206164815.10084-1-alex.bennee@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Subject: [Qemu-devel] [PATCH v4 21/22] fpu/softfloat: re-factor compare List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: richard.henderson@linaro.org, peter.maydell@linaro.org, laurent@vivier.eu, bharata@linux.vnet.ibm.com, andrew@andrewdutcher.com Cc: qemu-devel@nongnu.org, =?UTF-8?q?Alex=20Benn=C3=A9e?= , Aurelien Jarno 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 Reviewed-by: Richard Henderson --- v2 - minor re-factor for better inf handling v3 - fix renaming of structs/functions v4 - use is_nan --- fpu/softfloat.c | 134 +++++++++++++++++++++++++++++------------------- include/fpu/softfloat.h | 2 + 2 files changed, 82 insertions(+), 54 deletions(-) diff --git a/fpu/softfloat.c b/fpu/softfloat.c index cb889a7a84..8fc1c2a8d9 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -1784,6 +1784,86 @@ 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) { @@ -6885,60 +6965,6 @@ 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) { diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h index 35df225a55..cebe37b716 100644 --- a/include/fpu/softfloat.h +++ b/include/fpu/softfloat.h @@ -251,6 +251,8 @@ float16 float16_minnum(float16, float16, float_status *status); float16 float16_maxnum(float16, float16, float_status *status); float16 float16_minnummag(float16, float16, float_status *status); float16 float16_maxnummag(float16, float16, float_status *status); +int float16_compare(float16, float16, float_status *status); +int float16_compare_quiet(float16, float16, float_status *status); int float16_is_quiet_nan(float16, float_status *status); int float16_is_signaling_nan(float16, float_status *status); -- 2.15.1