MIPS: math-emu: <MAXA|MINA>.<D|S>: Fix cases of input values with opposite signs

Fix the value returned by <MAXA|MINA>.<D|S>, if the inputs are normal
fp numbers of the same absolute value, but opposite signs.

A relevant example:

MAXA.S fd,fs,ft:
  If fs contains -3.0, and ft contains +3.0, fd is going to contain
  +3.0 (without this patch, it used to contain -3.0).

Fixes: a79f5f9ba5 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction")
Fixes: 4e9561b20e ("MIPS: math-emu: Add support for the MIPS R6 MIN{, A} FPU instruction")

Signed-off-by: Miodrag Dinic <miodrag.dinic@imgtec.com>
Signed-off-by: Goran Ferenc <goran.ferenc@imgtec.com>
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@imgtec.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: Bo Hu <bohu@google.com>
Cc: Douglas Leung <douglas.leung@imgtec.com>
Cc: Jin Qian <jinqian@google.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Petar Jovanovic <petar.jovanovic@imgtec.com>
Cc: Raghu Gandham <raghu.gandham@imgtec.com>
Cc: <stable@vger.kernel.org> # 4.3+
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/16883/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This commit is contained in:
Aleksandar Markovic 2017-07-27 18:08:51 +02:00 committed by Ralf Baechle
parent aabf5cf02e
commit 1a41b3b441
4 changed files with 22 additions and 6 deletions

View File

@ -243,7 +243,11 @@ union ieee754dp ieee754dp_fmaxa(union ieee754dp x, union ieee754dp y)
return y;
/* Compare mantissa */
if (xm <= ym)
if (xm < ym)
return y;
else if (xm > ym)
return x;
else if (xs == 0)
return x;
return y;
}

View File

@ -243,7 +243,11 @@ union ieee754dp ieee754dp_fmina(union ieee754dp x, union ieee754dp y)
return x;
/* Compare mantissa */
if (xm <= ym)
if (xm < ym)
return x;
else if (xm > ym)
return y;
else if (xs == 1)
return x;
return y;
}

View File

@ -243,7 +243,11 @@ union ieee754sp ieee754sp_fmaxa(union ieee754sp x, union ieee754sp y)
return y;
/* Compare mantissa */
if (xm <= ym)
if (xm < ym)
return y;
else if (xm > ym)
return x;
else if (xs == 0)
return x;
return y;
}

View File

@ -243,7 +243,11 @@ union ieee754sp ieee754sp_fmina(union ieee754sp x, union ieee754sp y)
return x;
/* Compare mantissa */
if (xm <= ym)
if (xm < ym)
return x;
else if (xm > ym)
return y;
else if (xs == 1)
return x;
return y;
}