softfloat: fix {min, max}nummag for same-abs-value inputs

Before 8936006 ("fpu/softfloat: re-factor minmax", 2018-02-21),
we used to return +Zero for maxnummag(-Zero,+Zero); after that
commit, we return -Zero.

Fix it by making {min,max}nummag consistent with {min,max}num,
deferring to the latter when the absolute value of the operands
is the same.

With this fix we now pass fp-test.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20180413140334.26622-2-alex.bennee@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Emilio G. Cota 2018-04-13 15:03:33 +01:00 committed by Peter Maydell
parent 38e83a71d0
commit 6245327a36

View File

@ -1704,7 +1704,6 @@ static FloatParts minmax_floats(FloatParts a, FloatParts b, bool ismin,
return pick_nan(a, b, s);
} else {
int a_exp, b_exp;
bool a_sign, b_sign;
switch (a.cls) {
case float_class_normal:
@ -1735,20 +1734,22 @@ static FloatParts minmax_floats(FloatParts a, FloatParts b, bool ismin,
break;
}
a_sign = a.sign;
b_sign = b.sign;
if (ismag) {
a_sign = b_sign = 0;
}
if (a_sign == b_sign) {
if (ismag && (a_exp != b_exp || a.frac != b.frac)) {
bool a_less = a_exp < b_exp;
if (a_exp == b_exp) {
a_less = a.frac < b.frac;
}
return a_sign ^ a_less ^ ismin ? b : a;
return a_less ^ ismin ? b : a;
}
if (a.sign == b.sign) {
bool a_less = a_exp < b_exp;
if (a_exp == b_exp) {
a_less = a.frac < b.frac;
}
return a.sign ^ a_less ^ ismin ? b : a;
} else {
return a_sign ^ ismin ? b : a;
return a.sign ^ ismin ? b : a;
}
}
}