diff options
| author | Aleksandar Markovic <aleksandar.markovic@imgtec.com> | 2017-07-27 18:08:52 +0200 |
|---|---|---|
| committer | Ralf Baechle <ralf@linux-mips.org> | 2017-08-29 15:21:55 +0200 |
| commit | 3444c4eb534c20e44f0d6670b34263efaf8b531f (patch) | |
| tree | af52c4f4afae51b1568475d8b0c81303567ba241 /arch/mips/math-emu/sp_fmin.c | |
| parent | MIPS: math-emu: <MAXA|MINA>.<D|S>: Fix cases of input values with opposite signs (diff) | |
| download | linux-3444c4eb534c20e44f0d6670b34263efaf8b531f.tar.xz linux-3444c4eb534c20e44f0d6670b34263efaf8b531f.zip | |
MIPS: math-emu: <MAXA|MINA>.<D|S>: Fix cases of both infinite inputs
Fix the value returned by <MAXA|MINA>.<D|S> fd,fs,ft, if both inputs
are infinite. The previous implementation returned always the value
contained in ft in such cases. The correct behavior is specified
in Mips instruction set manual and is as follows:
fs ft MAXA MINA
---------------------------------
inf inf inf inf
inf -inf inf -inf
-inf inf inf -inf
-inf -inf -inf -inf
A relevant example:
MAXA.S fd,fs,ft:
If fs contains +inf, and ft contains -inf, fd is going to contain
+inf (without this patch, it used to contain -inf).
Fixes: a79f5f9ba508 ("MIPS: math-emu: Add support for the MIPS R6 MAX{, A} FPU instruction")
Fixes: 4e9561b20e2f ("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/16884/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch/mips/math-emu/sp_fmin.c')
| -rw-r--r-- | arch/mips/math-emu/sp_fmin.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/arch/mips/math-emu/sp_fmin.c b/arch/mips/math-emu/sp_fmin.c index 7915b9430f68..42ec4315e66c 100644 --- a/arch/mips/math-emu/sp_fmin.c +++ b/arch/mips/math-emu/sp_fmin.c @@ -202,6 +202,9 @@ union ieee754sp ieee754sp_fmina(union ieee754sp x, union ieee754sp y) /* * Infinity and zero handling */ + case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF): + return ieee754sp_inf(xs | ys); + case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_ZERO): case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_NORM): case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM): @@ -209,7 +212,6 @@ union ieee754sp ieee754sp_fmina(union ieee754sp x, union ieee754sp y) case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO): return x; - case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF): case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_INF): case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_INF): case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_INF): |